By early game, I'm guessing you mean until chapter 10.
Canter of course, if you can buy it. I always buy it for Alear. It is very useful to reposition him and use his personnal skill.
I always give my Vander Hit+10 from Sigurd. If I can I give it to Boucheron too.
Build +3 is also very good to fix some units, like Chloé or Alfred.
Healing Light on your Qi Adept if you are keeping it. Not so sure about Staff Mastery but it's cheap so why not. You won't be able to inherit Canter anyway.