As far as Utsusemi: Ni, I never really considered that an expenditure. I have NIN as a possible support job, but I have never subbed it. Utsusemi: Ichi was all I ever planned on needing if I did since I didn't figure I was ever going to be blowing through shadow recasts nor do I actually see myself getting to 75 any time in the next few months to worry about it.
Trust me, when you are facing a mad greater colibri who just woke up and your light shot timer is down, Utsu: Ni is your best friend.
COR's get asked to pull in meripo a lot, especially in casual pickup groups. In order to do the job properly you only need 3 things: Light staff, light cards and Utsu:Ni. Beyond that, anything works. I've pulled with bullets, hyoton;Ichi, mamoolbane, darts. That doesn't matter so much. It's the fact that you can keep mobs slept for the melee and can tank them for a bit when light shot timers are down.
But I agree, you are a ways from 74, esp if you are going to stop levelling for a bit to raise alchemy crafts, make some gil, finish some genkai.
But seriously, buy a stack of iron bullets and macro them in for WS. 6 more levels is along time in the 60's