i just got lolletta, is that other five star any good? i think i'll just stick with her, rerolling was a pain
She's not the ideal starter, but she's actually more powerful than Nimpha. What makes Nimpha so wanted is her Treasure ability. Her actual stats are pretty subpar [some 4* are even better than her in that regard], but she's still an irreplaceable unit for her abilities.
You can always go ahead with your Loletta account and just befriend a few Nimpha users. That's what I did [I started with Aludra]. Given her popularity, she's pretty abundant. Re-rolling is definitely a headache on iOS, so I'd say if you get a 5* as your first/second recruit, go ahead with that account.
A bonus of getting Loletta is that she has a chain quest, which unlocks another 5* after completing [Phoena]. Phoena, despite being a Cleric, is a horrible healer, but she's extremely valuable as a sub [once she levels to 60]. In fact, she's pretty much one of the quintessential subs for end-game, even in the Japanese version.