Freepace 2 is indeed still going after how many years? Just recently I saw that someone again released a new pack of models for people to use.
I also think that PGI could make use of the communities creativty a lot more. Need textures to be redone? Bet someone will love to try his hands on that. Seen some people, just for the fun, use AI reworking on older game textures with some good results.
Need new maps? Open up the Map editor, that comes with the engine anyway and let people go crazy. Setup some rules like "no p-enis shaped buildings" and stuff.
For FP I can imagne that some folks would even do some custome campaign with maps, rule sets, some small story and so on.
I mean when it comes down to it I guess you could reduce PGIs workload to just moderateing forums and monitor submissions of what people create and have a small staff for doing technical work.
Only stopping stones that I can see in this are
A) Legal problems. Don't know what rules are there in place and how a companie is responsible for what is done...also if moderated you filter out that stuff anyway.

You actualy need to work with the community, so moderators and Q&A people become more importenant.
C) Someone has to admit that their vision hasn't only gotten them so far and they need a new approach.
D) Technical limits, also I don't realy see that as a problem. There exists a mapeditor and the other graphics where most likely also be done with Photoshop, GIMP, whatever...that people have more or less also access to.
Beside that you can setup rules like Maps have to be size X or images can't be bigger then X-MB