Well, to blabber a bit, the Firefly change has made it more important that either
A) The target is a distraction to force some enemies to waste turn 1, and isn't crucial to the main plan (late dungeon Marcus, Nina3, etc.)
B) The target really is a true tank who won't die. (Ephraim, Ziggy, FF1 Knight)
C) The target has some evil ability that makes them a psuedo-tank (JANE, FFT Monk's Hamedo as the more balanced example)
Actually, Onix isn't a bad combination of both, as who cares if he dies but he randomly spoils physical damage well.
Even with the revive nerf, this new Firefly is still quite powerful, and I'd cheerfully pay points for it. Having a distraction round 1 is pretty huge, and tanky Dungeon teams with overwhelming MT damage or status tend to slay the party anyway. (Also, count me as totally on the bandwagon for
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Some people brought up FE8 Ewan earlier. Think he'd be pretty neat, but he's a 0.5 point pick. Compared to Moulder, he's a complete puny on floors 1 & 2 (early healing and tankiness is at least something, especially in a team whose healing comes later, compared to Pupil Ewan's bad damage with no durability and getting doubled), and isn't as good stat-wise as you might expect. He's average speed, but has horrible Con, so is below-average when using "heavier tomes" like Luna and even more so when using Nosferatu (yay FE for not making sense; how are *spells* heavy?!). You can only buy Nosferatu 5 plot battles from the end of the game anyway. On the bright side, his stat caps are nice and high, so he continues to get better on Floors 7-10. And Gleipnir is a nice nuke even if it *completely* tanks Ewan's attack speed (and isn't happening until floor 7 or so due to requiring an S in Dark). Also, as usual, Dark gets all the "interesting" spells, with Eclipse for damage, Luna for RES-ignoring, and Nosferatu for the (slowish) drain game, and it's generally hard to find much good dark-typed damage?
Think I'd see Ewan as something like:
Floors 1-2: Pupil
Floors 3-4: Shaman (Eclipse, Luna)
Floor 5: Druid (Nosferatu, the various Healing and Arcane spells)
Floor 7: Gleipnir
I assume most people would go with the Druid route, as Summoner is kind of DL fail, and there are plenty of other options for Arcane magic.