I think the licenses to get it bronze isn't the really problem, but to gold them! that's difficult.
When I got GT3 (about 2/3 months ago) I just started to get al my licenses. Took me a few hours, not difficult. Now I've finished all the races (only one left...cote d'azur, GT f1 champ.) I started to concentrate me on the licenses...I've got to do 3 int. A license tests, then for rally still 3 tests to get it gold...and 10 pieces for the S-license...but that's gonna be very difficult! As I still don't have all the tests in silver...
but: the most difficult is the S-8, but you can make it a lot easier! just pick the manual gear shifting, that's much easier!