@andypuk1980a
It's not just you. I see it in my game too. I'm not sure what causes it and it can be annoying due to the time it takes for the portraits to load. And if I open the relationship panel, all the portraits have to reload there. If your sims have met a lot of other sims, that actually takes longer to load those than the portraits in map view for me most of the time. I don't think it's CC related though. Idk for sure, but I think it might be more dependent on the number of households and sims you have rather than anything else. More sims and households simply means that there are more portraits to update and load on startup. The more you have, the slower it will be to get all of them loaded.
And if you delete the localthumbcache file, which holds all the portraits in your save, then it takes even longer as the game has to regenerate every single one plus all the icons for the cooking menus, etc., the build catalog and CAS catalog.
The thing I have noticed though, is that lag in my game is much better than it has been, and I typically run now with higher FPS once I get through the initial loading of the save and the household I chose to play. It might start slow but after a few minutes, it picks up and the game plays smoothly. For me, that's a big improvement over what it has been at times in the past. Although, on occasion, I do have to quit and reload the game to get better FPS.
But tbh, I don't think the game is causing some or even most of that. I have found that if I start the game with other programs running, then my game loads and runs slower and I have FPS issues that will cause me to quit and restart, sometimes multiple times. If I start the game first before starting anything else, then I usually don't have any problems that way. I think what happens is that other apps will grab resources that the game wants to use if you start them first, so I start the game first and then other apps. Since I started doing that, I don't have anywhere near as much lag or FPS issues. So, you might want to take a look at what you have running before you start the game and start the game before starting other apps.
Hope this helps.