I had some ask me what I thought on Discord and my response was too long to type it all out there, so here it is all written out.
Graphics
Graphics don't mean much to me (I still think EQ Project 1999 looks fine) so I'll get it out of the way quickly.
Despite not being into the voxel look (never played Minecraft) I was surprised to find that very quickly I didn't even really notice the art style any more. In fact, several times I even found myself thinking things looked very pretty, especially with certain lighting effects applied! There were even a few animations on these blocky enemies that were pretty good. The effects (spell particles etc) were well done as well. The art style also makes it very easy to see stuff and what's going on which I appreciated.
First person view is done better than in M&M (doesn't have the issue of my own hand flying in front of my face a lot when running with certain races, or the camera suddenly shifting back into 3rd person because I stood too close to a wall). It's worth noting that first person is the default, and I ended up spending more time in that mode than 3rd person (out of habit from playing EQ1 more than anything), while the opposite is true in M&M due to the above issues.
My one issue was that I found myself less engaged with my own character's appearance than I might normally be. So it doesn't have as much of that "wow I hope one day my character can wear that cool-looking armor" that can be a fun factor in other MMO's. Even stuff like being a spell caster you can't really wear a "robe", it's just a robe texture slapped on the same blocky model.
Otherwise, I don't think the art style was as much of an issue as I worried it might be and I don't think it would bother me. It may even grow on me.