How would specificity affect illusion and shapechange variants?

[Whizbang Dustyboots]

How much affect would locking down the nature of an illusion or shapechange spell have on its duration? Instead of, say, disguise self or alter self having the broad range of choices available to the caster, it always made one look like a certain race and, furthermore, just approximated your features as a member of that race, so that it couldn't be used to appear as a specific other individual of that race.

Would disguise self as halfling go an hour per level instead of 10 minutes per level? Longer? Shorter?

 

[BlackMoria]

I agree - a hour per level vice 10 minutes per level sounds about right and would be what I would use.

 

[Whizbang Dustyboots]

I agree - a hour per level vice 10 minutes per level sounds about right and would be what I would use.

Eeeeexcellent, thanks.