Painted first then wrapped to change the colour scheme for airshow work.This interests me. If vinyl is lighter than paint, it makes me curious how it would exceed the balance limits, unless maybe the vinyl was applied over an existing full paint job.
From my research and inquiries around here, most advise that vinyl sticks much better on a metal plane if there's at least one coat of paint underneath. This actually works fine for me since I'm hoping to use vinyl just for trim colors after painting the aircraft white. There's a local company does vinyl wraps on vehicles, and I was going to ask if they'd be interested in doing my plane. That's still quite a ways down the road for me right now though.
The main advantages of wrapping over paint is no finishing with vinyl, the ability to change colour scheme quickly and ease of adding complex shapes and accents. Weight depends on the weight of vinyl used against the skill of the painter. Paint can be light with only a couple of coats of high quality (expensive) paint.