Great to have a thread like this!!
As a DM/Player, I appreciate both aspects of gaming, and think we all ought to be more appreciative of what a DM does in order to generate and maintain a campaign. I asked my players and this is what they said.
My strengths:
1) Background Story and Detail--The players feel like they are in a real world, and that things are happening that they can influence and be influenced by.
2) NPCs--Personalities, real, alive, engaging, complex, with their own motivations. Not particularly impressed with self-perceived heroic qualities. Makes interactions more complex.
3) Hand-Drawn Maps--Yep, I draw them all.
4) Willingness to Discuss Rules (Within the bounds of the "2-Minute Rule)--We figure something out and if we find something out that is different in the rules, we let everyone know. Plus, if there is something we need clarification on, we do it. No one knows everything.
5) Refusing to Compromise the Integrity of the Campaign--This has led to a couple of arguments and lots 'o' emails with a couple of players, and we were able to reach an understanding. The game and the campaign must go on.
6) Hanging Out With Everyone Beyond the Game--Yep, we all have lives and interests beyond gaming

and some of us go fishing, some go to bars, some to concerts, some play music, etc.
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