As for using regular ships, my fleet anti-healer, which DDIS suggested to take on the role as an anti-healer build. (I made minor changes in the build since then).
Anyway, this ship (used by my scientist), for the first time, allowed me to tank a tactical cube. I was very surprised, and happy. This tanking occurred in Khitomer elite.
It still hasn't changed. About a year ago I ran a 5 minute ISE with a defunct STF channel, STF Veterens which had been a very good time at pre Season 6 (possibly a record). That was when I met who would become my future fleet makes when I practically forced myself upon them due to how well we synergized.
Quite frankly most of my "best" weren't actually good as far as STF's go (in mission terms). This is because I tend to enjoy them most as a "Trek" battle than a "do this, do that, mission achieved" thing. So, in many the optional was gone, took a lot of time and many people made error after error (I error frequently, too) that made it much more difficult. But so much fun.
Withouth great detail, for instance, I remember one that I got in late. The people there were half-way through. I go full-impulse to get there asap and I see this guy almost destroyed being attacked by a sphere. I rush for him and drop out of impulse between him and the sphere buff him and fire on the sphere, destroying it a few moments after. I bet he could have handled it anyway, but it had a very "Sir, it's the Enterprise" feel from ST First Contact. Loved that moment.
Best recently, was a Hive Space non-elite. A day earlier I'd joined one (my first post-LoR) with four tacs and we couldn't get the first unimatrix below 95%, so when I saw three (other) sci's and an engineer warp in, I wasn't thrilled. But, it was one of the more efficient Hive Onslaughts I've participated in. The queen was getting sub-nuc'ed like clockwork, it was a fun one to do.