Yeah definitely keep with Wither Bolt as your at-will, learn Whitefire soon as possible because it's a great early game nuke spell with a short recharge and can stay with you for a while. For your second recharge lightning spike is fine until you hit level 2 - then you can either replace it with Blight Orb for extra hard hitting nuke (if you're okay with just wither bolt for aoe), go Grease to supplement your summon and whitefire. You could also supplement with more white mage powers like entropic winds to give you more damage type variation or blessing for a team buff.
Your encounter spells are really limited to Flame Spirit or Spirit Veil - or Kiyoko if you choose that route. So you can either go a support mage type or full damage early, and then your options expand when you hit level 4. Stat wise focusing on Willpower, Cunning, and Presence gives you the most options, but you can swap Presence for Agility to go full glass cannon and then replace your summon with a damage based encounter at level 4 and above.
I really like keeping Atugia as a tank early on because she has damage misdirection shields and a dot - she definitely got stronger now that stances autoapply at the start of the fight. Once you hit level 4 I really like having Soul Arrow as a replacement for Whitefire because a hard hitting nuke with a healing component on a short recharge is just really strong (as long as it can hit the opponent - doesn't work on constructs or anything with high mental resist). Good luck, fellow mage!
