One more question-how would I have it do something else done if I hold shift or ctrl? Such as just casting a grounding totem, which can be vital if I get jumped by a caster.
Are you trying to do something like this?

/castsequence [mod:alt] spell1,spell2, spell3; [mod:shift] grounding totem; otherspell1, otherspell2, otherspell3

If you think about it, a /cast is simply a /castsequence of length 1 you can keep daisy chaining them together with ";" all you want.