I'm not sure if this has ever been suggested or not, but does anyone else think it'd be fun to have the ability to participate in major battles from Star Trek history? For instance, the Battles of Wolf 359, Cardassia, Chin'toka, and Deep Space Nine, to name a few.
Not only would this give upper-level players more to do with relatively little new content required (most of those maps and ships already exist), it would give also Federation and Klingon players new opportunities to work together. Plus, the concept of reliving old battles could give Klingon players more opportunities for PvE combat against Cardassians, Romulans, and the Federation, which couldn't hurt.
Anyways, just a random idea. Would be interesting to get everyone else's thoughts on the matter. Not sure how they would explain this in-game, but I am sure the guys at Cryptic could come up with something like "Q Encounters" to make them fit.
They could use the Guardian of Forever for this if they wanted to. Plus it might be nice to have such missions not only be in major events, but peripheral to them, e.g. running interference/picket duty to protect major events from being affected. They could have the players intercept and hold off a force attempting to delay the Klingons from joining the battle to retake DS9. Folks wanting the NX class in get could get that via another time travel mission placing the players as active participants in the temporal cold war...or we could all just forget that travesty ever happened (the temporal cold war I mean, some of the series was ok :p). Still, if cryptic is dead set on putting in the NX, I would find that an acceptable way to go about it.
I think the major concern people would have about doing missions from the past via the Guardian of Forever is that by entering the *actual* past, we would, in theory, be interfering with the future... unless you were going back to ensure history proceeded as it was supposed to.
But, if these new Fleet Actions were handled in such a way that they were simulations or tests from Q, then we could still get involved without actually altering the past... plus we could do them over and over again
As for doing Enterprise-era missions, I think they could work if they were also simulations of some sort like the Fleet Actions above, or if they were Guardian of Forever missions that mandated that you use an NX-style vessel to complete it. Personally, I would LOVE to do missions in an STO-era Delphic Expanse of some sort... perhaps the Sphere Builders can try to take advantage of the instability in the region by attempting to reconfigure space once more?
Again, would be cool to hear what other people think.