Defile |
Personally, i think the manifestations are a good thing.
Ive played the uber wizard with Improved Invisibility and Fly cast and its actually not much fun just easily blowing everything up after a few times. Ive also been the DM on the other end of that. What i saw from both perspectives is the rest of the players at the table bored ore annoyed.
To me its more an issue of making casters have to think a bit tactically. With manifestations still being visible even if the caster is not makes the caster have to think about positioning and what spells they will cast.
Rules wise the Invisibility spell says it makes the 'caster' non visible which it does. The manifestations are not the caster. An invisible caster holding a torch would still leave visible light and smoke once it left the torch. Even spells that the caster does not 'wield' would still be visible. Blade Barrier is a good example of this. Casting that spell would handily identify which square the caster is in while still leaving the caster defended by Invisibility.
Id just use the rules of the Clever Caster feat as a base for diminishing the manifestations. Never mind with making anyone take the feat and just make it something any caster can try.
But again, just by base rules only the caster themselves is made invisible.