The Elder Scrolls games have literally dozens and dozens (hundreds?) of optional quests and guilds and so on, which usually give good in game, relevant rewards. Worth a look and won't break the bank.

So, you basically only enjoy the game by making it as unenjoyable for your opponent as possible?

That is definitely one way to play Bloodbowl, and it also explains why you need to play it online instead of with friends - and it explains the concede rate you are receiving which is not punished in the casual BB2 ladder system. Many people (who, just like you, might not have endless time) put a lot of hours of good effort into building their favourite players and team compositions and prefer conceding over losing them to some ... person who doesn't even like the game for itself but just for ruining other's experience.

If you are tired of people conceding, try using the Champions ladder, Concedes are limited to 5 per Season there!