What Matt said. When i play a 6-Max tournament i try to dominate the table as much as possible. Play as many hands i can, but ofcourse, adjust if they don't allow me and play back at me. In a decent 6-Max table they won't allow you to do so and you'll slowly start bleeding chips. But in most 6-max games i play i win most chips by winniny many small pots because they simply play to tight, and i can play overly aggresive. When they finally do play a decent pot against me i can sometimes stack them 100-200bb deep because they stack off with top pair.
In general yes you play more hands and youll have to, but how lose depends on your table which also applys for a full ring.