Many of us have already gotten to New Game + and maybe beat the game obtaining 1 gold star on the last few levels. The problem is once you reach the home stretch spec becomes EVERYTHING. If you want to beat the last 4-5 levels with all Stars and a Perfect rating you will need to do the following.

• Beserkers - Need to make sure their spec contains all of the AOE Abilities, Whirlwind isnt as important as maxxing out the Furry Crit and Bleed values.
  
• Archers - Archers are so lame end game due to the fact that the worms can evade 70% Ranged attacks or so. My advice use them as debuffers for the bleeds and posions and make sure their AoE Abilities are maxxed out. Pierce armor isn't as important of a trait if you are careful placing your Paladins.
  
• Monks - Max all healing skills, Max Inspire and Max blind + Ether Flash
  
• Mages - Freeze and Slow maxxing will be the most important at this stage in the game. Use Mages primarily on lanes were alot of armored or worms will be.
  
• Paladins - Possibly your most important unit to place well and spec well - Make sure you get as much Armor Break as possible and max your knockback and stun and their corresponding abilities as well as Sword Training.
  
• Dragons - I rarely use Dragons but they are extremely effect at AoE Packs for Dragons max out their fire balls and fire breath as well as their +ATK abilitly. Think of them less as melee fighters and more as long range artillery.

Itemization in this game is often severly overlooked and not really done well by players. Make sure your items are appropriately used. Put your Paladins with the Thorns return armor right next to the creature spawns supported by a monk or two. Make sure your mage with with the 3x worms and 3xspitters staff is placed very well in order to minimize the effect of those buggers. Secondly make sure each weapon and bow and staff goes on a character you will remember to place in a spot that maximizes the item itself.