A real ST exclusive gem is Bolo by Meinolf Schneider of Oxyd/Dongleware fame: http://www.mobygames.com/game/bolo
Play in it monochrome (hi-res) mode for much better gfx.
There is an abundant demoversion. The full version is harder to find. The full version might be on D-Bug #128 or on Automation #323B or on both.
It is a bit hard to start it from these disks in monochrome hi-res, because the cracker intro and game selection screen gfx are corrupted in monochrome display. I got it working in Steem this way some years ago.