You should travel all the passes on the west of Khomas Hochland! If you like passes and there are some you haven't been to, they all offer something special and awesome in a unique way.
Speaking of mountains and passes, Zarishoogte is an other-wordly sight but best seen from the Maltahöhe side ;-).
I found Naukluft Mountain park absolutely fascinating, the various contrasts in terrain and the relative coolness in the deep gorges.
Ganab campsite (#3 I think it was) is very special for its sense of openness and solitude.
Not sure if they still operate, but the rubber-duck excursion off Walvisbaai provided an experience of a lifetime with dolphins at play almost as far as the eye could see.