1. At my last job our boss used to say "There are no such things as problems, only opportunities". This lasted a while until someone pointed out that we were currently facing an "insurmountable opportunity". Obviously most of the features suggested over the years
could be implemented by essentially rewriting the entire game engine, but that's not really practically possible is it?
You tend to see this when a new user joins the forums and make a post with a title along the lines of "MASSIVE NEW FL FEATURES!", containing a list of features that'd be fantastic to have but couldn't be implemented without several million in the bank and a five year development program. Believe me guys, if we could have built a way to control your own trading empire a la X2/X3 then we
would have done already...
In my opinion it's better to let a modder know that an idea is, as far as we know, impossible, rather than give them false hope and make them waste several months attempting to make it work.
2. Regarding the gravedigging point, that's valid up to a certain point. However, when people are asked "How do I increase cruise speed" for the thousandth time I'd say they're well within their rights to say "Go search for it".
3. I don't really see what you're getting at here. If an inexperienced modder posts some good,
practical (see point 1) ideas then surely the more experienced modders would take the idea and run with it. I can't really see any further way to do what you're saying, aside from forcing established modding teams to take on inexperienced team members in the hope that they'll have some good ideas...
Besides, I'd think that experienced modders would have more idea of new features that could be added to the game, and more importantly they'd know which can be implemented and which are, to all intents and purposes, impossible.