Things to fix
Two(or more) pieces that are the same should be able to be placed in either spot.
Some levels require the level to be completed in a certain order instead of just completing the sequence puzzle.
Sometimes you have to reset the puzzle and do it again to complete (this may be related to the previous problem)
Did 24 and looked up the walkthrough since everything I tried didn't work, turns out I was right the first time but I still put it in that order and it still doesn't work
there should be a reward for "No more moves" or at least on timed stages. I feel heavily punished waiting for it to rearrange and have lost because it. One time it said "no more moves, too time to rearrange, I made a match and I got no more moves again. I shouldn't be punished for their being no more moves especially when it's the rearranges fault. most games reward for running out of moves due to the fact if you ran out of moves you were probably slowed from there being lack of moves and also some skillful players can try to negate moves (aka complete the puzzle)
you should make note that Fool's gold doesn't include upgrades that cost faction coins, unless it's suppose to in which case you need to fix it so it does.
In the challenges where the player is missing can you make it so one of the allies is playable? it's so boring to have to sit there and watch your allies fight. Or even allow the player to play the different characters?
I must be lucky since I haven't had too much trouble with Dim's indestructible levels but I did have a lot troubles with some of the other levels (like the over packed ones that requires all things to fall down just perfectly
 "Realm Grinder"){kind=icon}
 "Sequence"){kind=icon}
 "Battle for Blood"){kind=icon}
 "Mighty Knight"){kind=icon}
 "Ninja Slash"){kind=icon}
 "HUEBRIX"){kind=icon}
 "GunBall 2: Emperor Revenge"){kind=icon}
 "Crush The Castle 2 PP"){kind=icon}
 "I Wanna Win!"){kind=icon}
 "Warp Game"){kind=icon}