Ok so out of the units I have so far, which ones should I focus on raising?
I cannot comment on all of them, but if I was cherry picking units to evolve from that list I'd pick:
Darvanshel - Great all around unit, has single target BB along with a multi target SBB, both of which come with invaluable 50% damage resistance for 1 turn.
Vael - Just got updated to 6* (Ragshelm), but probably more of a late game unit.
Orna - Fire & Lightning element buffs and a not too shabby 45% crit buff on her SBB.
Kuda - Also has a 40% crit buff on his SBB, great stats and I guess an easy unit to spark with as well.
Narza is also great for having the same 50% damage resistance along with status nullifying buff in his BB.
In other news, I pulled like 5 times during this event. Got:
Nick - "Poor man's Zelnite" - purely an item farm leader, but he has a better item drop rate buff than Zel! I'll definitely use him during event dungeons.
Faris - Decent addition to my crit squad, too bad about the Guardian type but still an okay unit nonetheless.
Uda - has a BC drop buff in his SBB - not sure if I'll find an use for him outside a mono-thunder squad . Breaker type at least.
Ramna - also a breaker but nothing special, if I ever make a mono-fire squad I'll put her in it.
Shera - So happy I got her! The only unit I wanted besides Lucca. Not leader material but really just a better Darvanshel with an ATK boost on her SBB. Now I have two mitigators with single target BB attacks which coupled with Ultor should up my tanking game quite a lot.
Sadly no Lucca
But.. now my dream team that I could assemble (for hard content) would be:
Ultor lead
Darvanshel
Shera
Lilly Matah or equivalent BB gen unit
Last unit would be either Tia for maximum heals or an unit that gives the correct element attacks - for example Lucina if I need Earth.
This should give me 2 mitigators to cycle through, and Ultor's taunt as well, which is a bit fiddly manageable.