Each DM and player have their own preferred pacing. I try to be open, if the group wants to go adventuring and get to it with minimum fuss, no problem, I got all the dungeons and the dragons. If they want to spend a little time exploring the town and getting to know the NPC's, that's great, I got all the plot hooks and side content.
Where I usually draw the line is if they want to split up with each character trying to get a solo adventure while I have to worry about keeping the other players involved in the game, which is the problem I used to have with "going to major city to shop" sessions- I put my foot down now and say you can either get with me on Discord or we can pass emails, or you can stick with the group because I've been the player who got locked out of the game for hours on end in the past because the DM wanted to pull people into another room (this happened in D&D but all the damned time when I played VtM) and it sucks.
I don't have patience for PvP actions (I tell 'em to let me know what happened, I have better things to do).
I despise one PC hiding information that the group should know (If you don't trust these people why are you traveling with them?).
I also try to move along the old "taking prisoners who will always turn around and backstab us" debates. I usually have captured NPC's be very clear about what they are going to do. If the ogre you saved is loyal to his tribe, he'll probably tell you what you want to know, but he's going to go back to his tribe if you let him go.
I also draw the line at out of game/out of character drama. I don't care who sleeps with who, if that means you can't game together, don't show up to game, thanks.
Oh and as a rule, I don't accept drugs and alcohol...wait, what was I talking about?
Oh right, pacing. Yeah so I'm flexible, but if I feel like people's precious time (especially mine) is being wasted, I'll push to move things along. Note that if everyone is having fun, that's never wasted time (as in, they're laughing, smiling, engaged, and into character).
(If they're frowning, looking at their phones, and seem frustrated, I don't know, I'm not a Betazoid, but I think that's a good sign someone isn't having fun.)