A little bit of all options, if we're honest
At least one character has made a comeback, with her original powersets, but INV/EM tank was a frustrating powerset to level to 50 the first time round, so she may only crop- up in RP sessions.
A couple of characters I never really got to play much due to their powersets being released too close to the shutdown have come back (Rad/Time corr, SJ/WP brute) as they were.
Then there's the "changed name" characters.
My peacebringer has had to be slightly renamed due to name clash (not that it bothers me personally.) She's essentially staying the same with the variation in name,
My main EN/EM blaster started off as a simple rename due to (again) name clash. Then I decided that I wanted to use EN/MA as that more closely fit her original concept from waaay before Martial arts in blast was a thing. As I played, I realised she no longer fit her new adopted name, so I rechristened her, and created a new EN/EM blaster with that name (and same power vfx)
I then got bored, my altitis happened, and I creates a BS/Shield scrapper using the same power vfx, vanguard weapons, and a similar outfit, named her in the same theme, and so, out of me wanting to have my cake and eat it, I ended up with Project BRIGHT, a multi-phase project to create Expert-System Assisted Quantum Waveform-Engine Battlegear (Phase 1: Ranged Combat (EN/EM). Phase 2: Frontline Melee (BS/SD). Phase 3: AI Type Human-mimic Combat/Infiltration Frame (EN/MA)
That whole business has taken a life of its own now, due to my insatiable need to create stories.