In the event someone wants to use a custom technique, derived from a spell they already have (Ex. Oka Hoken, which is based on Sagitta Magica), how would someone do that?

I've simply added different incantation (not so if a ki technique like Kagami's Fire Spray) and changed the effectg to suit the difference.

But that seems a little obtuse dont you think? Why pay the same amount of points for a similar technique to the other one?

I like Psyren RP's idea of Technique Branching:

-If you wanted to use Raika Hoken, you would just list it as Branch Technique: Raika Hoken (8) under Sagitta Magica(5). You would only have to be +3 MP for the difference to get the technique. However, in PvP, it would function like a charge attack, you perform on first, and then the other

That's the exact same as One Piece RP. :l

When has that been a bad thing?

I would like this too.