Besides mods and the listed expansions, are you using any CC, including purchased and/or ARR'd store content? Excessive amounts of CC can cause lag, but combining packages can help to resolve this.
Also, have you patched your base game and expansions? I suggest using the MTS Patcher program.
No other CC, I got rid of it all in the first install and have been using the MTS program since the start. EA can't code/outsource coding at Origin to properly accept game keys never mind patch updates. Attached screenshot of packages in use.
http://simswiki.info/wiki.php?title=Game_Help:Package_File_LagIf your CC is merged, use the separate files for this test.
Go to the process monitor section, filter by process name ts*.exe, then path names containing .package. If there's any CC being accessed more often than anything else by a large margin, kill it and see if it improves your situation.
If you've done this already then nevermind.
Edit: Grammar.
No I didn't try that actually. Excluded path name shared as well was getting a load of fullbuild1.package, fullbuild0.package and deltabuild but I figure this is EA an normal. When I changed the path to 'is' C:\Users\Martin\Documents\Electronic Arts\The Sims 3\Mods\Packages I only got one result. Only the .package screenshot attached cant attach log or other screenshot due to size limits.
I don't think any power in the universe can truly prevent TS3 from lagging. It's just dogawful as far as code optimization goes and chugs no matter what you do. This is easily the dominant reason I barely play anymore: It's just LOADS AND LOADS OF LOADING followed by chugging. The worst of it is that it doesn't even appear to be using up most of the computer, it just chugs for no apparent reason at all.
Haha I wondered as much. SimCity, The Sims, Rome 2 Total War it seems to be becoming a norm to release a near beta. Fine if your a small studio and in fairness some try to fix it but when EA churns out store items before fixes it's obnoxius.
EDIT - ProcMon log
http://dfiles.eu/files/w5qef4o08]http://dfiles.eu/files/w5qef4o08