I spend like 500 hours in Diablo 3. But I don't have Reaper of Souls. It is even worth to play without add-on? In every Blizzard game add-on is so integrated and gives you so many enhancements in gameplay that I seriously doubt if it is possible to play clean Diablo 3.
I would highly suggest getting the RoS expansion without it your very limited in what your able to do and farm. Unfortuantely without the expansion we also wouldn't be able to offer any power leveling or gold farming services either.