#1-Once you buy a tower, and click the tower again to try and put it back, you lose the tower and can;t get another. i bought a 500 credit tower to start, clicked the tower again to put it back, and was shut out from buying anymore. no credits, and no tower to place. So, i had to restart the game. Please fix this. this also cost me 1500 credits when i bought a big tower. i almost quit playing at that moment.
#2-Upon the second playthrough, i noticed there were some places i couldn't set a tower. they aren't color coordinated because it's a green area and i can set a tower in another green area. Something to show where you are able to place towers would be nice. a different color red for no/green for yes, grayed out for no, and full color for yes, something to that effect.
#3-Different enemies with various strengths would've been better than the same enemies travelling at faster and faster speeds. also, a couple of different maps would be good.
if this is your first TD game, not a bad start. just add some tougher guys and more maps and you've got a good game. overall, it's got playability, but not repeated play. it;s got a lot of work to be as good as the best TD games on this site. It's a good start, just make some tweaks.
3/5, 3.5 stars