Tanya's final suggested build for her, after the discussion and including her offered 3-bronze-coin loan, was:
Taller form, slightly younger-appearing face, but disguised by tallness.
Elaborate costume, however she ended up designing it.
Psychic specialty- Don't change.
Fist weapon- Spend 1 brz to make it a magic staff or wand of some sort instead.
Major power- Focused Assault- Don't change.
Minor powers- Escape Mechanism (spend 1 brz, replacing Disguise), Overworld Shift (spend 1 brz, replacing Monstrous Metamorphosis), Absolute Direction (spend 1 brz, replacing Magic Handbag), Enhanced Sustenance (severely reduced need for air, water, food, sleep), Cosmic Heal (spend 1 brz, replacing Gifted Magic).
Gold coin- Spend to gain Regeneration extra major power.
Stats before coins (in costume/out of costume):
With two silver and four bronze coins left, giving her two +2s and four +1s to distribute in terms of stats (in costume only).
Tanya recommended she reach 8 in Magic but not go over that, and recommended Agility and Vitality be the focus for what she has left, but didn't specify an exact layout.
Or optionally- Instead of Regeneration use the gold coin to pick two minor powers, but none of the options discussed struck her as critically important.