And if we only play one or two of the eps at a time, then the lag would not be an issue, either. Also, I actually think that if we played without all that store content (at least for me) - the game would come up quicker and run smoother. I actually have what one would consider a top of the line fast computer - but it doesn't do anything to have a great computer if the program is not written properly. However, the more stuff you pile into a game, the more cluttered it becomes and the game can't handle it (has nothing to do with the computer at all). So there are work-arounds for some of the issues, but unfortunately, not all of them. I think the major issues with lag, etc. and just overall glitchiness came with the latter games, starting with Seasons and just getting worse with each additional ep; to the point I think the programming of the game itself had a complete breakdown with the last few eps - especially with Islands.
All of that said, I really do miss the concept of The Sims 3 and the open world. It was outstanding - we just added to much into it and stuffed it too full. If I can just make myself play with less, I think I would still enjoy The Sims 3 more than The Sims 4.