Eirika has IVs too. Titania is basically red Ursula. 1 spd 1 atk difference. The only other real difference is Blue horse tome has way more competition.I feel V!Titania is fine because of her movement/weapon type. She's mediocre, yes, but honestly most ranged horses aren't great unless you're minmaxed or have a great prf. SM!Eirika is more minmaxed, and better than V!Titania, but not *that* much better. If you're going the bladetome route, Eirika only has 2 more speed on Titania.
Aversa stands out most in AR however. It doesnt stop her from being good elsewhere, but AR is where she stands above. Shes also the only flying mage that can be reasonably merged, so thats really nice.ok sweet, thx pal! that way I can specifically invest into 1 or 2 of the chars
For other Grail units, WCecilia is extremely good. Naesala is excellent but doesnt work in all teams. Masked Marth is one of the best of the older units. Dragon Slaying is quite nice right now. Navarre is also really good, but requires extremely high investment to take full advantage of.