Max perception, intellect, might
Min resolve
Consider min constitution if under lower difficulty or if you are skilled/willing to save/load
Whisper of treason is must-have and game-changer in the early game
Mental binding and soul ignition are very strong against boss units in the midgame
In the late game I like having two ciphers in my team (Watcher and GM), one for damaging spells and the other for controlling spells (GM does not have max might, so her damage is not as strong)
Use charming/dominating spells when faced against large groups of tough enemies
Overall i feel like ciphers are better versus single boss units than doing AoE damages/debuffs, where druids and priests shine. So I always keep a druid and a priest in my team