You did not waste AAs.
You need Spell Casting Mastery all ranks as soon as possible. It saves a ton of mana on ALL spells you cast. It is the most over powered AA ever thus there are no more ranks of it.
If you use Fire like I do, always get DD/Crit, Pyromancy, and Ro's when you can.
Personally, Perfected Invis I can't believe I ever lived without it.
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After 16 years, I'm not listing every friggin character.