Im a huge Warhammer40k fan, but I never tried collecting and painting miniatures, the scope is massive, so many armies so many choices. Played most of the games from that universe, specially Dawn of War series where you can paint your armies in custom colours, very detailed but nothing beats real life painting I guess. So instead of Warhammer I went into Magic the Gathering, less work, same amount of money spent.
There are quite a few armies, and I doubt the Orks will be my only one. The amount of decisions that have to be made for a good MtG deck seems way higher to me though.