It took me six days to hit max level of this expansion, which actually feels longer than previous expansions. Part of that was losing a day of playing while Blizzard suffered DDoS attacks from China. Part of it was spending more time doing other things when I was playing, like fishing and archaeology and hunting for treasures. And maybe, just maybe, part of it was from actually reading most of the quests and watching all of the cutscenes this time around.
I only really did quests in two of the zones, too. So I still have plenty of quests to run around and do for fun. I managed to get enough garrison resources while leveling to upgrade to a size 3 town, but I didn't have enough resources after that to build new buildings in all the slots I gained by getting bigger. I didn't build any of the buildings that generate extra resources, and I built one that I think costs resources. I also found a lot of treasures, and killed a lot of rares, to get extra resources. So I suspect getting a resource generating building early on would actually have been a pretty good idea. But if I'd done that I wouldn't have been able to level my followers as fast, and I only have 2 of those at max level so far... So maybe if I'd gone the other way I'd have lots of resources but all my people would be underleveled? Who knows!
Hitting level 100 opened up so many quests around my garrison and in the area I as leveling that I actually ran out of space in my quest log. And it wasn't like I had low level quests kicking around clogging it up! I can't remember the last time I hit the quest log limit... So clearly there's a lot of stuff still to do.
I must say, I'm still happy I got this expansion.