If you can buy spells in chargen, the entire Magic priority needs to be rewritten for Magicians. The only reason it currently makes sense is if their spells are restricted.
That said, since I consider Initiating something for experienced runners, I wouldn't allow it in chargen.
Nothing about 6th Editions priorities makes much sense, so why should the Magic column be an exeption?

Good lord, I hope that Karmagen comes back so more peoply abandon that mess ...
That being said, I don´t see any balancing problem at all with mages being able to buy spells at chargen. If you really want to set off the additional spells off from the spells from the priority table: Why not make it mandatory to buy the spell formular as well? Thats my current houserule for Karma-bought spells at chargen (I transferred that one over to my improvised Karmagen System as well.)
Initiation (and Submersion) is on another page, though. IMO, that should continue to be a big step in character advancement. In fact, I think that it´s way to easy right now, especially when you look at the severely overpowered option to get one P.P. as an Adept.
(It doesn´t help that the balancing for the different Initiaton / Submersion Techniques generally is all over the place, either. I mean, just look at the Fixation Metamagic. Why does that even exist? As a final reminder that Alchemy will never be a worthwhile option?)