After playing the new magus last night and getting completely raped (2nd lvl and really s%+!ty rolls), I think there should at least be an option for the magus to pick whether he is prepared or spontaneous. I like spontaneous casters better and I think that if you gave them a few more spells per day and a spells known table, they'd still be balanced.
One of my biggest problems last night was running out of spells way to fast. I know this happens but even with 1 more spell that I could have casted for the day the fight may have been a LOT different. Especially since you have to constantly make concentration checks in combat. I had 3 spells for the day and only 2 got off. Better than average, but if you get less than average spells off in melee you're boned since that's your thing.
It was better to take the AOO but with being 2nd lvl, one hit is deadly enough (last weeks game, I played a character and he was taken from fully healed to 1 hp past what was required to kill him, not incap, but KILL him, so when I brought this magus in I wasn't taking any chances).
At this point, the class (and Alt-class options) are finalized, typeset, formatted, and probably being given their final edit before going off to the printer.
It'd be nice if there was a spontaneous-casting Alt class, but at this point it's either already in the book, or it's too late.
I'm curious - did you use your spell points?
Semi spontaneous casting comes in at later levels with more abilities and such, it's a second level character, it's going to be hard to manage it's resources.
Sorcerors are 'born' with magical ability that manifests its self in spells.
Magus's and wizards 'study' spells. But in a sense the arcane pool Is the Magus's spontaneity and it works rather well.
The fight could have gone differently if you were a spontaneous caster? There is the arcane duelist bard, a similar class, but look at what you loose by not going magus and going bard.
There are trade offs, but you can't get both.