fire beastmaster
felar savage
half-drow explorer
and human hunter

i ranked a ton in battlefields (tracked the mobs to the indoor caves and perfected rebounding strike and shadowstride), aran'gird, ruins of maethien (the large nightwalkers are all in cave indoors), and storm giants tracking to the cave in veran. i never noticed any difference.

even with the half-drow explorer i got good mileage out of wanderlust and storm giants tracking to the indoor mountain room.