SpringMapEdit already allows you to sculpt land:
http://springrts.com/wiki/Maps:SpringMapEditBut if you're going to make a map with a pefectly green texture and a hand-sculpted terrain, it's going to look awful. It would only sit there looking bad if we included a mission made this way.
Mission Editor has been around for years and nobody did anything serious with it at all. I said to Quant 'Just make a mission editor, Other games had things like DOTA and such created on their mission editors! People will definitely make missions if you give them the tools.'
I was wrong. MissionEditor may be a bit buggy but it's MORE than enough to make some good missions. There are very few people willing to contribute their time seriously to this project and I don't think Linux users are that much more likely to contribute (We have NO permanent devs who run Linux, or maybe we'd actually have decent linux support!).
So, right, again, it falls to the long-term devs who have skills that are much better used doing other things to learn all the tools, spend all the time, and make this happen. The money is appreciated, really it is. But your time and effort is more valuable than your money. We already work on this game for free (Or, the rest of the devs do, I rarely have enough time).