No idea who said feral/rogue/priest is easy to play is smoking. It can put out a ton of pressure and force other comps to go defensive however if the rogue and feral do not play perfect it is one bad stun/fear away from being an easy game for the other team.
Easiest team to play is TSG in terms of pressure and random button pushing. RMP, RLS, and WLD all take some form of skill to play well. In all honesty pick a team and play 100 to 200 hundred games get to know your partners and then anything is easier.