Since I play the Overlord, I've noticed that I've had a very fighter/strategy game-ish mentality to Descent: there are winners and there are clear losers. This has lead me to a rather formulaic playstyle where I have a small but IMO powerful selection of Open Groups from all the expansions that I field on every scenario. This has given me plenty of wins against the heroes but I'm slightly afraid this will have a negative impact on enjoyability on the long run.
How many times would you like to face Golems in a row as hero, but on the other hand would you ever as the OL field Zombies or Cultists against your opponents unless you specifically want to make things easy for them? Why field a "tier 3" monster when you could put in it's place a "tier 1" monster?
This of course yet again underlines the sad fact that if the OL wins, one guy is happy but if the heroes win two to four guys get to whoop and celebrate.