Crap, my Ephriam is probably also very low on SP because I only pulled him near the end of his banner.I'm also thinking of turning Ephraim into a lance-using Eirika. I'd give him Hone Speed 3 and Rally Defense. I think I'd also eventually want to replace his Moonbow with one of the healing specials, and give him Quick Riposte. He only has 384 SP, though, lol.
What do you think you'll put on his A slot? I keep bouncing between Defense, Res and HP. HP would make him more durable overall since his resistance isn't great, but Defense might make him very very durable against physical attackers. Res would make him better against mages and dragons, but on the other hand I could always use a different unit to lure those if necessary.