Basically Aspected mages get a pretty raw deal in RAW.
- Starting magic of at best 5,
- no free spells,
- and getting the skills in a skill group, which if I understand RAW you can't technically break until you are spending your karma (i.e. if you have skill group 4, you can't use 2 starting skill points to raise one of the skills to 6, you'd have to spend 5*2+6*2 = 22 karma instead.
- and on top of all that, astral perception rather than projection
Whenever I try to come up with an aspected mage I tend to end up actually making a full mage and taking the Incompetent negative quality to block one of the other key groups, and just not buying a skill in the third.
I'm not saying that you can't make a good aspected mage, just that the hassle ends up not seeming to be worth it to me in general.