I like this game. Here's how you basically win:
Pick an alliance based on the options in your 1st 2 rounds. Always pick as many heroes as you can in round 1.
After you pick an alliance combo route, only buy heroes that you absolutely need, use 5 gold to go to level 4, and then DO NOT level up or roll anything (unless free) until you have more than 30 gold. Don't go below 30 gold, and if you need to to buy a hero that will take you below 30, wait for the fight to start.

Alliances to base your game on (alphabetical):
Brawny - If you go for it, go all in. Don't go past level 5 until you've maxed Juggernaut, and then hide him in a corner. Make sure other heroes and items don't steal your brawny kills.

Brute - Goes great with anything. get an odd number of brutes and look for the Tier 3 fedora item to put on a ranged hero. Many alliance combinations and great time to use demons or champions.

Fallen - Risky early unless you're very lucky with a Terrorblade. Start with a throwaway team. Get to level 8 or 9 quickly and pray for a Wraith King. You're probably gonna lose before you find him.

Knight - Stay at level 5 until you've maxed Chaos Knight and then do whatever the * you want.

Mage - Get to level 7 as fast as possible and go for all 6 slots. Combo with Dragon.

Poisoner - Get Venomancer, Dazzle, Bounty Hunter, Queen of Pain, Alchemist, Shadow
Shaman, and Slark. Or just pick Veno and combo whatever to see where it goes. Wroks great with Brutes & Lycan.

Rogue - Stay low level to max heroes. Max Meepo and put blink dagger on him until you get a good t4 or t5 item. Shiva and Horn are the best.

Savage - Get to level 7 and combo with a Slark with a Mask of Madness. Get blink dagger(s) to protect your slark. You can also go for a high-level overwhelm strategy, but you'd need to be lucky to get through late game.

Spirit - Stay at level 5 until you max a few and combo them with Legion Commander, but only put him in if you don't have any other spirits to put on the board. Once they're maxed, pair with spectre and void alliance at level 7.

Warrior - Put a vengeful spirit in front center. Get to level 7 fast and get all the warriors. replace the venge or go to level 8+ for better damage dealers.

All other alliances should go with one of the above.
Shamans and summoners win early but lose late.
Never get a hero just for a swordsman, human, or hunter alliance.
All 4 slots of vigilant can be great or hurt if you're not careful.
Healers, Shadow Shaman, Spirit Breaker, and/or Vengeful Spirit need to be out in front.

If you're going to rush a phantom assassin, it's not going to win you the game alone. But if you do it, you need to be lucky early, stay at level 3 as long as possible, and spin early. There's practically no reason to get a phantom assassin unless you're going to max her with a bounty hunter and a meepo.

Generally don't use a Legion Commander without a Demon alliance on the board, and don't put too many demons unless Spectre is maxed out.

Base your game around tier 2 and tier 3 heroes. If you're level 7+, don't be scared to sell any of the tier 1 heroes you've collected if they're in the way. Stay at level 5 to focus on a t2 hero and move to level 7 for a t3.

I like this game. Here's how you basically win: Pick an alliance based on the options in your 1st 2 rounds. Always pick as many heroes as you can in round 1. After you pick an alliance combo route, only buy heroes that you absolutely need, use 5 gold to go to level 4, and then DO NOT level up or roll anything (unless free) until you have more than 30 gold. Don't go below 30 gold, and if you need to to buy a hero that will take you below 30, wait for the fight to start. Alliances to base your game on (alphabetical): Brawny - If you go for it, go all in. Don't go past level 5 until you've maxed Juggernaut, and then hide him in a corner. Make sure other heroes and items don't steal your brawny kills. Brute - Goes great with anything. get an odd number of brutes and look for the Tier 3 fedora item to put on a ranged hero. Many alliance combinations and great time to use demons or champions. Fallen - Risky early unless you're very lucky with a Terrorblade. Start with a throwaway team. Get to level 8 or 9 quickly and pray for a Wraith King. You're probably gonna lose before you find him. Knight - Stay at level 5 until you've maxed Chaos Knight and then do whatever the * you want. Mage - Get to level 7 as fast as possible and go for all 6 slots. Combo with Dragon. Poisoner - Get Venomancer, Dazzle, Bounty Hunter, Queen of Pain, Alchemist, Shadow Shaman, and Slark. Or just pick Veno and combo whatever to see where it goes. Wroks great with Brutes & Lycan. Rogue - Stay low level to max heroes. Max Meepo and put blink dagger on him until you get a good t4 or t5 item. Shiva and Horn are the best. Savage - Get to level 7 and combo with a Slark with a Mask of Madness. Get blink dagger(s) to protect your slark. You can also go for a high-level overwhelm strategy, but you'd need to be lucky to get through late game. Spirit - Stay at level 5 until you max a few and combo them with Legion Commander, but only put him in if you don't have any other spirits to put on the board. Once they're maxed, pair with spectre and void alliance at level 7. Warrior - Put a vengeful spirit in front center. Get to level 7 fast and get all the warriors. replace the venge or go to level 8+ for better damage dealers. All other alliances should go with one of the above. Shamans and summoners win early but lose late. Never get a hero just for a swordsman, human, or hunter alliance. All 4 slots of vigilant can be great or hurt if you're not careful. Healers, Shadow Shaman, Spirit Breaker, and/or Vengeful Spirit need to be out in front. If you're going to rush a phantom assassin, it's not going to win you the game alone. But if you do it, you need to be lucky early, stay at level 3 as long as possible, and spin early. There's practically no reason to get a phantom assassin unless you're going to max her with a bounty hunter and a meepo. Generally don't use a Legion Commander without a Demon alliance on the board, and don't put too many demons unless Spectre is maxed out. Base your game around tier 2 and tier 3 heroes. If you're level 7+, don't be scared to sell any of the tier 1 heroes you've collected if they're in the way. Stay at level 5 to focus on a t2 hero and move to level 7 for a t3.