Well I openly stated that my impressions of the game are based upon very little experience.
Also, it's not a MMO (as I corrected myself) but it's very MMO-like in that you have a hub city that you always have to go to for various reasons, as well as teaming up for quests and lots of grinding for materials.
I played for about 4 hours last night with my friend and bugs aside (very poor co-op that's always disconnecting or now showing friend sessions) I actually had fun. So far I think the monsters are pretty easy to read and I can avoid getting hit most of the time. My friend who I was playing with kept dying because he wouldn't roll out of the way or anticipate certain attacks. My opinion of combat has improved since yesterday, but I still have major issues with the game.
1. The current state of multiplayer is trash. Friends often cannot join my online session, nor can I join theirs sometimes. Even when we do manage to get in the same session I often cannot join quests that my friend posts up, and not because of level requirements. I just get an error and can't join. This is a commonly reported problem>
2. The amount of time that it takes to use items while in combat is ridiculous. You have to put away your weapon and come to a full stop just to drink a potion, which makes you a sitting duck. Also, the monster AI seems to be programmed in such a way that normal 'aggro' keeping techniques from other games simply doesn't work. The monsters seemingly go for anyone who is trying to heal / sharpen / etc rather than whoever is dealing the most damage or being the most annoying.
3. Lack of monster HP bars sucks IMO. I know that damage is kinda shown on the monster models but it's not very accurate and you never know just how close you are to killing anything... you just keep attacking until it dies. Also, the monsters are damage sponges and either have a shitload of HP or player attacks are weak AF.
4. Even after I quit the game there will sometimes be a MHW process still running in Windows that I have to manually shut down via task manager, which takes up some CPU and makes my fan run non-stop unless I shut it down.
5. Friends cannot play through story mode missions together because the game requires both players to be finished with cut scenes before you can join or someone else can join you. What this means is that if you're playing with a friend one of you needs to be higher level than the other to not waste time, or you both have to start the quest individually and then once the cutscenes are finally over one or more people need to exit that quest and then join someone posting the quest. It's really convoluted and shitty.
6. The in-game voice chat is terrible.
7. A lot of 'heavier' weapons are so damn slow that they are nearly useless because by the time your swing even finishes the monster will be in a totally different spot. So far I'm sticking with the dual knives/swords because it's fast and I can actually hit things.
8. Weapons seem to bounce off of creatures a lot doing no damage at all. I can understand if it is a really thick bit of hide or armor but some of the hitboxes are silly, especially when using a slow weapon. My friend was SCREAMING last night about this and also constantly running out of stamina.
9. I haven't been able to upgrade my weapon in some time because I am lacking some material that shows up as

at the smithy, and I have no idea what it is or where to get it.
complaints aside my attitude towards the game is improving a bit. I just wish that the combat was better in certain ways and that the co-op wasn't so janky.