I would love if they brought back Pharoah's Quest/an adventurer theme, Atlantis/Aqua Raiders, Rock Raiders/Power Miners, plus a fantasy-castle-esque theme (best castle waves they ever came out with)...
Edit: oh, and bring back Space Police III
Those were the good old days.
Oh yeah and bonkles.
Also, contrary to your list, I wouldn't want elves to end. It has surprisingly good techniques and builds. Only downside is the minidolls.