I miss mostly good racing simulators. Although there's now VirtualGP2 for MOS, but nothing more. Some rally, f1, gt games anyone? There's tons of them on PC, but nothing on Amiga.. latest are practically from a500 era.
Morax: I think those genres you mention are the best supported on Amiga

For recent RTS games: Knights&Merchants, Warcraft2, Earth2140 and mission pack, Exodus, Napalm, MoonBase, Red Mars (?)... for space sims at least that Descent Freespace 1 and 2... for adventures The Feeble Files, ScummVM games

, Nightlong, Simon the Sorcerer 2, Codename Hellsquad, 6th Sense Investigations, Abduction, Double Agent, Lost on Parrot Island, Teen Agent.. all 1998 or newer. Recent for Amiga if not for others

There are other genres which haven't got any releases for 10 years.