To reply to your other part, which I'm sorry I missed:
Magnitude I'm handling with Talents available to Smart/Ded/Charismatic. We have a pure-class Smart caster. Dabbler is a feat that anyone can take (nobody did). Student of Wizardry / 1st Mag / 2nd Mag / 3rd Mag are all a Talent tree, with Student of Wizardry giving its usual magnitude jump along with making the magic skills class skills (though we removed Resistance, because none of us liked it for our game). 1st Magnitude is the next talent in the tree, with a pre-req of 8 Ranks of Use Magic, meaning he can pick it up at 5th level (Wizards get it at 4th level). Same sort of thing with 2nd and 3rd, each with Use Magic ranks putting them at one level AFTER a BCCS wizard would pick them up as class features.
Beyond that, I left Talent as a feat and put it on the Bonus Feat list for all three classes. Our 5th level caster is 1st Magnitude with Spell Energy Resevoir and Talent x 2 (Air and Force). I added Use Magic to the Savant list and removed the Talent Focus feat, just to see how it would work. I wanted a little more power in my game. It's DIFFERENT magic, not so much LOW magic. We also have a Craft Magic system where pretty much anybody can learn to make magical items based on crafting rolls and XP costs alone. Currently he can cast alot of pretty powerful effects, as he has (effectively) Talent Focus to any spell he has. But, as I said, casting times keep him very much in check during combat.
--fje