Instead of Invisibility granting fixed Stealth bonuses and See Invisibility granting automatic countering of that bonus, why not make it a simple caster-level-based bonus?
Invisibility: + (caster level) bonus to Stealth rolls when moving, doubled when not moving.
See Invisibility: + (caster level x2) to Perception checks to perceive creatures hidden at least in part by invisibility.
Glitterdust: Imposes a penalty equal to (caster level x4) on Stealth checks for the duration of the spell.
Faerie Fire: Similar to glitterdust.