Proposed Houserule for BC Options

[Laesin]

I'm considering the possibility of moving the game I run over from 3rd to 4th edition. Unfortunately one (among many) of the issues that I have with 4th edition is the way that background count works. So I'm considering this variant. Background count applies only to drain codes for casting within them. i.e. Any spell cast within a BC will have its drain code raised by the BC, unless the BC is appropriately aspected in which case the drain code is reduced by the BC to a minimum of 1. Spells brought into the BC will have their force adjusted by the BC inversely. Adepts will lose effective magic for the purposes of calculating powers effects but not for how many powers they possess.
Does anyone foresee difficulties?

One other possibility I considered was raising the threshold for casting spells by the BC,However I considered this too harsh.