Well, the point on encouraging anyone is a tricky one, cause:
on one hand, no one in even not exactly right mind should ever be naive enough to think that even the totally accurate simulation playing is going to make him a better pilot in real life..
(sure, one can always use it as a sort of "this might do for this situation" - watching how the simulation reacts to certain situations and ways of overcoming them in relation to real life flights, but i don't think anyone would go out and try them irl base jumping right away - you practice first until very least you feel comfortable doing it (unless you find yourself in a situation in which you're most likely are going down anyway and everything's an option that might safe your life - so you're basically dead, unless a miracle happens... sort of like that kid who did in real life world of warcraft "play dead" on a bear and the bear left him alone))
wingsuit licenses and gear are really a luxury a very few can afford, it's not like a kid with blanket is going to jump of the window cause he played a game... (i mean, there's always one like that, we can't help it and we all know it however we don't want to admit it, he would've anyway with or without the game) therefor the game and real life have two different targets (as i imagine, grown man who have the capability to get into the wingsuits don't play games much, and even less take anything they see in game as an inspiration to gamble your life over)
On the other hand:
- one must think about the unconscious aspects of brain memorizing and inspiration, cause even if one plays a game, even a true simulation, however you see that as other than real jump, it's going to affect your flying on a subconscious level making a pilot actually take more risks than he would without playing before - but the same thing applies to watching anyone fly eighter irl or on yt video or in game or even simply imagining the flight itself.
This makes it a factor that is far more complicated than simply getting inspiration from game.
Being able to participate in such activity would rather suggest that the pilot is most likely a mature human (above 24yo i think would be a good shot, maybe even about 30), enough to understand the risks he/she takes, and at very least got the basic know how to do it, and does it on his/her own mind - once again, being maturely aware of the risk and actions taken. If one is such a person and have some self criticism is the other thing, but the responsibility for actions and awareness lies within each individually.
You can do whatever you want, labels, movies, campaigns, restrictions and ban the activity for ever and ever and there will always be people doing it, both thinking it through and not. There's always someone that wasn't quite prepared, that something went wrong, we can't help it no matter how much we would want to.
Volo, being more or less the simulatior game, have the unique opportunity to capture the attention of both sides - the young people enjoying the game, and the actual pilots, making the ethics of it quite difficult to settle over. I have no doubt that You (The Creators :D) have a heart in the right place and that the whole community suffers over the deaths, but it's not really something that can be affected by any mean - it's one owns responsibility to go in prepared and aware of ones doing as much as possible - the everlasting problem of doing ones' homework. No mean will make a difference in this.
What goes to Volo in game - i think there should be an option of graphic content/children-friendly mode selection. Personally i'd like very much to have some kind of a splatter gfx when crashing, even the simulated severed limbs, death can be fun in game and it's a good way to both see that the situation would've gone BAD irl; and that it's cool to respawn. That's a part of what games are for, to simulate and stimulate both victory and failure.
The graphic content off could be used when one just wants to chill in game.
Keeping the record on the statistics would be cool, maybe even scientifit to a certain extent. Keeping the track on how many jumps player did in total, how many of them went good and bad, what was the highest number of safe jumps (jump -> flight for X -> landing alive), what is the current number of consecutive safe jumps, what's the rating of jumps, what's the time that player spent in air in total, maybe even the top 3 causes of death (like a collision with rocks/trees/chuted too late)
As for any notice/warning in game, i think it's not necessary. Most people wont take the game (even true simulation) as a source of knowledge or inspiration anyway, even less of them will have a chance to put it into action.
Those who will, will do so on their own mind thus (hopefully fully aware) responsible for their actions. If you're affraid of the law suit - for the peace of mind a warning never hurts but if it's the care about people, well, can't really help anyone if they don't want to, however bad it sounds.
@fink the last sentence of your post above reminded me, that an option to create characters would also be neat, along with permadeath/recreational mode (for those who chill and for those hardcore grinders :P)