PC NA and EU have been running normally for me today, playing from the UK. No issues at all. Indeed, that's how it's been since launch if I'm honest, but then I don't PvP, group or do trials. Nor have I ever used addons.
The only time I've had actual screen freezes were on my MacBook Air during the recent Oblivion event. Twice when I tried to take a wayshrine to the Fargrave City District, and once when I tried to take a doorway from the Shambles to the Fargrave City District, my screen literally froze-- the Ouroboros in the bottom right corner of the screen stopped spinning, and I could hear the NPCs talking in the Fargrave City District as though I'd arrived without any problems but my display was literally frozen on the loading screen. Shutting down the game, restarting, and trying to log back in on that character on my MacBook Air had no effect-- the screen was still frozen. But I could log in on my other characters in Vivec City and Vulkhel Guard with no problem. And fortunately I was able to log in on the affected character on my Windows PC, after which (and after moving him out of the Fargrave City District) I was able to successfully log in on him again on my MacBook Air.
I also have a lot of issues with one of my alts who is currently stationed in Davon's Watch; the video and sound stutters, the NPCs and graphical objects take a while to load in, and the game as a whole seems sluggish and unresponsive. But after a few minutes, when everything has finished loading in, the game smoothes out and is playable again; it's just that initial period of logging in on the character that's the problem.
I also have problems of textures loading in very slowly, resulting in "missing" walls or buildings, sometimes even the entire Abecean Sea missing with the "dry sea bed" plainly visible, whenever I port to Gonfalon Bay in High Isle. Things get back to normal eventually, but for a few minutes it can be quite a view with all of the missing objects and textures, or in some cases with surfaces that get displayed with a series of trails created by the surrounding objects and textures as the camera angle is moved while I'm running or riding along. That isn't anything recent; it's been going on for a long time now. I don't know if it's a problem on my end (such as the graphics card, or the local game files, or the internet connection), or is something going on with the game, but it isn't a consistent problem with all zones, just certain zones or specific areas of those zones, especially the areas with high concentrations of players.
Where are your characters located? Have you tried moving them to someplace less populated to see if that improves how fast everything loads when you log in on them?