I think the ID based on levels was only for RBY, later gens dropped it to simply randochance? NINJANINJANINJANINJA: Nope, I'm wrong! Heh. Eh... Iunno, myself, can see it either way here. More likely to consider it an aspect of PKMN ID skills, though, yeah.
Re: Royal Paradise, what option would Frey take otherwise? Triple Harmony (Atk/Vit/Agility)? Gives him the same speed boost, tho... so eh. I wouldn't see that as speed twinking, either, but YMMV (if he was taking both solely for speed boosts (so Agility/something else) then sure, but these give other buffs that're also useful for him...).
And yeah, Swallow>Rainbow for averages also came up. I... suppose I'm willing to take Swallow because his best damage is magic, if it were phys I'd go Swallow RAINBOW as well. I just kinda am querulous on Rainbow, myself (it's a long sidequesty thing, though CHRONO TRIGGER DIFFICULTY and the game also tells you of it so eeeeeh yeah) and Swallow's a decently quick diversion. Seeing it as splitpath's -totally- fair, mind, but. Eh, again, YMMV.