The game is good but somehow I didn't enjoy it. I didn't really like my guys dying and all the sterile lab setting.
Graphics are good but screen seems cropped at bottom, it doesn't influence gameplay but looks ugly.
On what for a lack of better words can be described as "level 2" game suddenly goes to game over. Why? Did I use too many people? Was there a time limit? There needs to be an indicator to explain it.
Game should probably keep score on how many guys player used, perhaps have some achievements for having as little guys die as possible. I also think it should have a max number of guys per level, to see how many people you saved. Saving people would give this some emotional meaning, otherwise it is too cold. perhaps you should also choose your next guy based on looks and on whether you need a short or tall guy.