I always was a fan of Epyx's Impossible Mission II on the Apple IIGS (16-bit). I believe there was an 8-bit version for the Apple II as well. IM2 offered dynamically rendered towers (levels) - check out the Wikipedia article for more info and Google Images for screenshots.
Note, you'll want a working joystick for many of these games. You can find a "RetroConnector Joystick" on Tindie, which I use to make present-day generic USB joypads/joysticks compatible with Apple IIs. I own one of these, it's saving me wear and tear on the older authenic Apple II joystick that seems to work better with older Apple II Games.
As Bill references, there are a couple of compact Flash adapters available for the Apple IIGS which act as virtual floppy drives or hard drives. I own a "CFFA3000" (which is not currently in stock or in production, but you can contact Rick - the producer of this item to express interest in another manufacturing run). I also own a "Floppy EMU" - this is also a nice option, but I prefer the CFFA3000 for a few reasons.
http://gglabs.us/- produces some memory and video products for the Apple IIGS. I picked up both the 4Meg RAM option (pretty substantial for an Apple IIGS), and the RGB / Component video adapter.
I also built my own GBS-82x0 (GBS-8200/GBS-8220) video adapter to make the Apple IIGS work with present day LCD flat screens. This is my preferred video option currently.
Check out http://apple2online.com/index.php?p=1_70_inCider-Magazine- to read through some old InCider magazines if you'd like to get an idea of games of the day. Most Apple IIGS coverage didn't pick up until late 1986 or 1987.
If you'd like to invest a little more, I encourage spending $100 in the entire run of Nibble magazine on DVD ROM.