I can't speak to Angie's clothes because I honestly don't remember Colleen Atwood commenting on the look they chose for her (though, believe it or not, there are extras on the Blu-ray that I still haven't gotten around to watching, so there may be details in them) but so far as her make-up goes, I honestly do think that the intention was for it to be garish because it fits in completely with the fact that Angie's supposedly retained beauty in 1972 is very much a facade.
As for Depp's look as Barnabas, we know for a fact that mainly it was a backlash against the Twilight franchise (but then, so much of the film is a backlash against that franchise). Both Depp and Burton had commented on numerous occasions that they don't like how in too many current vampire films it's impossible to tell who the vampire(s) is(are) because they basically look just like everyone else. They wanted a return to what they consider the "classic" vampire look in books and films of yore.