The problem with the STF timer isn't that it makes Elite STFs impossible, it doesn't.
Well, I don't know about Ground, I don't do Ground.
The problem is that it's a pretty lopsided way to get people to play their roles... if that's what was meant to do.
It was never going to work, and indeed it hasn't: Cruisers stll don't tank, Science Vessels for the most part still don't support, save for a few attempts at crowd control with varying degress of success.
I still get singled out by every single Tac cube/Gateway/Donatra I engage and in most cases, they eventually make my fragile Escort blow up either by attrition or the rare one-shot while the USS Rainbow Odyssey stands idly
The other problem is that, quite frankly, they should be focused on one thing and one thing alone at this point: more Endgame content.
Not missions that'll be done once at most, not fluff like non-combat pets, not unnecessary adjustments to existing content, not lotteries; just endgame content.
A 2-year MMO with so little to do at endgame is way below industry standard.
It's a shame, space combat in STO is pretty fun, but apart from PvP and a meager 3 short missions, there's very little to do at endgame... which is made even worse by the speed of the levelling.