I thought it was OK but I didn't really enjoy it as much as other Bioware games. I thought the pacing in particular was tedious.
First of all I started the game but got bored and didn't finish. I just got divorced from the main story due to all the distractions which felt grindy, while I didn't enjoy the gameplay. I also struggled to get to know the companions, I guess a lot of their stories were buried with events further into the game which I didn't see, but they felt bland and I believe there were too many of them for good pacing.
I then tried again but there were serious clashes between the nVidia driver and Inquisition during cutscenes and the game was unplayable for a significant period of time. I gather this was actually largely nVidia's fault.
Finally I restarted and sticking mainly to the main story only I managed to play through and finish the game. It was about a 20 hour playthrough, so while I did a few extras, like some dragon killing and a couple of side missions, I am aware I probably only saw about 10% of the content. I assume there were companion quests for every companion, I completed 4 or 5 of them.
I did enjoy it so I started another play through intending to see more of the content I skipped in order to see the main plot. But once again I got bored and stopped shortly after skyhold so didn't really see much new stuff.
I tried MPer but found it was much laggier than ME3 MPer (which is a worry for MEA) and because I didn't really enjoy the gameplay I wasn't prepared to persevere and see if it was simply unlucky connections.
I generally don't like open world games or any game where you don't have a purpose. I never feel immersed in games you just wander around for the hell of it, especially when I don't really like the gameplay.
I can see why people like it, it just wasn't for me. I haven't bought or seen any of the DLC.