Scarf Lucario with Vacuum Wave? lolno
Since Lucario will be switchin' often, it might be a good idea to have it Physical instead'a Special so it can abuse Close Combat's (much higher) power. It has much better coverage moves on the Physical side as well (Ice Punch, namely), which is always important for a good revenge killer usin' a Scarf.
Speakin' of choice items, I've never heard of a Jirachi holdin' Specs or Band. It's base 100 stats aren't really good enough for choice items. Since Scizor already has a Band, you're better off givin' it a more traditional item like Leftovers. Oh, and add Wish t' that moveset. Choice item or not, Jirachi doesn't have the power to just throw around coverage moves and inflict dents. Jirachi's potential as a good Poke lies in it's defensive core capabilities/support movepool... well, that or abuse of Serene Grace and flinch hax.
Oh, and on that note, I wouldn't recommend any Calm Mind sets for 'Rachi. Your team does need a sweeper, but Jirachi sets up slowly by abusing momentum. Since your entire team is Steel-type, gettin' that momentum via resistances is that much harder, so a quickly set up sweep is needed. For example, Swords Dance Scizor (not that I'm tellin' you to change it's moveset, t'is just an example).