would love to cast my two cents into the Lyn discussion that erratically pops up in this thread now and then.
It's true that making characters mirror their respective game appearances is not a HUGE priority when regarding Vanilla Smash (prime example - Ganon). having said that, the PMBR is doing a brilliant job in regards to some of the overhauled movesets some characters now have (sonic, wario, pokemon) that are more or less lifted from their existing games or better interpretations of them (extremespeed on lucario for example).
now I'm aware that the fire emblem characters are not the best representations of their respective profiles from their games (if it were, Roy would look rather underwhelming in P:M, let me tell you..) and this trend seems to carry over into P:M. however, I think with lyn it would be a good chance to implement her in a way that would work around her profile in FE7. in all of my playthroughs, she has always ended up as being somewhat of a Glass Cannon - fast, hits hard thanks to a passabe strength stat and rather constantly respectable critical rate, but falls apart if someone so much as (g)lances at her menacingly. before I was familiar with the "Battoujutsu" style that ManlySpirit described in his (rather excellent) hypothetical Lyn write-up post, I always likened her strikes to those of Devil May Cry 3's Vergil using Yamato - quick, single, devastating strikes that always end with him sheathing his blade (with a somewhat large endlag, unless cancelled). while she is capable of using a bow upon promotion, not many people i know (including myself) actually made use of this ability - it wouldn't be missed, and it's one less article to worry about. being an athletic girl from the plains, I can also picture her not exclusively using her blade in combat - punches, kicks, sword while in sheath, ect.
With all this in mind, I think Lyn would be more suitable as a light character (like, almost kirby-melee light), and strikes rather hard with any attack involving her sword (with sizeable endlag). if my understanding of the way the clone engine works is correct, i'd think ZSS or Shiek would be good bases to go from - if that's how it works. i don't want to make out that i have no understanding of how this process works and i'm just talking out of my ass.