Before writing this review I need to state that Monkey Island has defined my childhood and put me on a path where making games became my sole goal. I'm not a purist so I don't hate Monkey 3,4 or any of the TellTale episodes and I don't see Ron Gilbert as the Monkey Messiah.
I will start with the Negative aspects and end with the Positives:
Mechanics & Complexity:
🅞 Combining wrong items no longer results in fun comments. In the current game, 99% of the times, only the items that work together can be combined. Even in low budget point-and-click adventure games, you would get replies for most of the item combinations
🅞 No more insult sword-fighting. Loved the insults sword fighting in the previous titles, especially in The Curse of Monkey Island and I was hoping to see something similar in here. In this game is very dull and dumbed-down. I felt quite disappointed that they didn't explore this feature further
🅞 Hard-mode is not necessary that hard. Puzzles felt quite easy. Probably the easiest Monkey Island in the franchise

Length:
🅞 Game feels rushed and somehow massively cut in scope to bare minimum: In 24h I finished the game almost 4 times and completed all achievements - I'm not a fast player, like to take my time and look at everything multiple times
🅞 Cog Island is proof of the cut content. An entire island with many locations that could have provided that variety the game needed
🅞 Very short chapters, even on Hard Difficulty: Chapters 1 and 4 are quite extensive, 2 and 3 are small-medium sized and the intro and ending are very short

Art & Narrative:
🅞 The Art style is an acquired taste. I understand that the bone-rigging type of animation is a lot less expensive, compared with 2D frame by frame. Maybe budget was a factor in this project. Overall I think it conveys the message and the vibe of the game
🅞 Due to the art style, sometimes little details are hard to read. Took me forever to understand that there is a knife in Gullet's back. Same for when he was upside-down, stuck in the rudder - I initially thought that's some sea-weed stuck in there and not a character
🅞 The new pirate leaders felt underwhelming and boring (both visually and story wise)
🅞 Scurvy Island could have been more interactible - Again feels rushed out and cut in scope


Narrative:
🅞 Fun Story with specific Monkey Island humor
🅞 The plot is very captivating. Would have loved to play a few more chapters.
🅞 Adding Murray was an excellent idea. The Demonic skull is one of my favourite characters in the entire franchise
🅞 Captain's LeChuck crew! All characters in the crew are very enjoyable and well written
🅞 The ending was great! No spoilers

Features:
🅞 Scrapbook Recap feature and the letter at the end of the game. Quite touching
🅞 Achievements and Trivia Book. That was a good way of making me spend a few more good hours collecting every card and answering the questions
🅞 Some of the puzzles were very creative but nothing challenging (Do yourself a favor and play the game in Hard Mode - I think the whole experience is a lot more cohesive and enjoyable)
🅞 Controller Support and UI are near perfect

Audio:
🅞 Voice acting is top notch. Dominic did a terrific job as well as the rest of the supporting cast
🅞 Soundtrack is fantastic. Peter McConnell's genius can be heard at every step

All in all I think it's a great experience for the 20$ price point. Ron and the team managed to achieve great results with such a small but passionate team. I salute the effort of the development team and I hope the sales prove Disney that this franchise is worth investing money in.
With a bigger budget I'm hoping to see bigger and richer places to explore, higher complexity in puzzles and narrative, as well as more refined animations.

Negatives/Things I did not like:

Missions and Narrative:
🅞 Visiting Rich People. The villa level design has changed and not in a good way. Before you could do the mission stealthily but now the safe alarm is triggered no matter what, ruining the stealth element. The whole charm of that mission in the original was to do it stealthily and leave with the glorious Silver Fletcher.
🅞 The bank job is not as exciting as in the Original. I still remember the thrill of casing the bank and hearing the plan from Paulie (who back then was more mature and intelligent and less of a man baby). In the Defintive Edition the mission happens very fast and feels dumbed down.
🅞 Lucas Bertone no longer sends you to do jobs for him. The treasure hunt mechanic for finding the rare cars is barely explored…
🅞 Lots of driving portions were removed to accentuate the movie feeling. I personally would have liked to have them like in the original.
🅞 Paulie and Sam's voices are very similar. Also Paulie seems too much of a crybaby and less of an impulsive gangster like we are used to.

Gameplay Cars:
🅞 The ability to Dodge/Ram cars which actually makes hand breaking redundant as the ability can make the car steer sideways and keeps it glued to the ground. Very helpful in the race mission (finished it very fast on Classic difficulty) but overall reduces the realism and makes driving feel arcade.
🅞 Car physics. I don't understand how a game that was released 18 years ago can have better car physics than what we got today. In the Original, depending on the speed and the angle of the crash, cars could lose wheels, bumpers. In the Definitive Edition you can crash at 120km without considerable damage to the car, character and other traffic participants. The cars that you crash into at high speeds fly like they are weightless (Classic Difficulty + Simulation driving)
🅞 Tommy is no longer taught how to lock pick cars. He already knows how to pick them all after a cutscene. In the Original he would gradually learn how to pick each type of lock for every model. They decided to go with the quick and cheap way instead of trying to add more depth to this mechanic that was so important in the original. As a fan I would have wanted to see a lockpicking mini-game like in Mafia 2 or something similar
🅞 The horizontal axis of steering is way too fast making any car feel arcade when turning, unless you modify the steering sensitivity when playing with a controller
🅞 There is no animation when filling up the tank at the gas station like in the original

Police behaviour:
🅞 The plate numbers are not remembered when evading the police like in Mafia Original and 2. The Wanted status is lost when going outside of the search area.
🅞 Pedestrians are not reacting to lockpicking. Stole over 40 cars and only once a pedestrian called the cops on the highest police difficulty
🅞 Killing an NPC in the middle of nowhere without witnesses will automatically trigger a police report and a car will be dispatched to investigate in blink of an eye
🅞 In the Original cops were using street police phone booths which is no longer the case in the Definitive Edition.

Enemies/AI:
🅞 Too many enemies that are too easy to kill even on the hardest difficulty.
🅞 Morello seems to have over 10.000 soldiers under his command for Tommy to kill while Salieri 10. For me this type of gameplay breaks the immersion and automatically makes it Arcade. I would prefer fewer encounters with less enemies... but those enemies to be 10x more deadlier. I was hoping the game would feel heavier where any confrontation can be your last
🅞 The AI is not very bright (Classic difficulty)
🅞 Companions can now absorb infinite damage like sponges without dying. The confrontations no longer feel tense knowing your team cannot die.

User Interface:
🅞 Too much guidance even on Classic difficulty. The game takes your hand and guides you to whatever you have to do. One of the strongest points of the Original was the sandbox vibe and the liberty it offered (more like in Hitman where you have to figure things out yourself). Missions feel a lot more scripted and linear and less exploration oriented.

Other:
🅞 Free Ride could have been a lot better by allowing to earn money and spend them on various things such as clothes, car improvements, weapons, etc.
🅞 Outfits are cool but not being able to mix and match clothes is a bit of a bummer. In 2002 would have been hard to implement but now, with the current tech should have not been a problem.
🅞 Some animation feel weightless, such as throwing a molotov or shooting the tommy gun.


Things done right:
🅞 Graphics. Extremely beautiful car models and characters
🅞 Narrative changes in some regards
🅞 Music and Score
🅞 Collectables and the fact that are displayed on the map when in near vecinity
🅞 Expanded Country side
🅞 Extreme Rides and Weapons side missions

Overall I think it was a great effort to bring back to life the masterpiece that Mafia 1 was but they missed on some key points, probably because this was treated as a side project within Hangar13.
I'm giving a negative feedback only to attract Hangar13's attention. Maybe they will take our feedback in consideration.
Either way, give it a shot and decide for yourself. The full price is more than decent