Aye, memories are easily the #1 cause for savegame bloat.

They do???? Yikes!

Are there any mods that restrict the memory system so that new memories are only added to the active household? I know there's something somewhere that limits memories to only the more eventful occasions, which I really should look into getting. I don't want to disable them completely but the system as it is sounds like a horrendous amount of bloat!

It IS a horrendous amount of bloat.

Just disable them completely, IMHO. You can still take photos of the events YOU consider significant for the scrapbook. Like, dunno, your sim's wedding or the kids' birthday parties or such. You'll probably choose a better angle and whatnot than the game does, anyway.

Oh, yeah, I've had the memories disabled completely. I also clear the cache files and screenshots every time I play. I emptied the Featured Items folder then made it read only so all those awful Store snaps are gone. I've followed pretty much all the great advice I've got here and it has definitely helped.

I play on a mid-grade laptop, but it does have a 7200 rpm processor, so I'm not so thrilled with the load and lag, especially as I have what I consider minimum cc.

Yes, the mod you want is right on this site: http://modthesims.info/download.php?t=446281 by velocitygrass, which you can tune to only capture whatever memories you choose to, all the way to none unless you manually capture them.

SIMs 3 is still not perfect and is riddled with broken features even with all update patches applied and all EPs added but the game is definitely worth playing especially if you care for the game's open world.

"Even with all update patches applied and all EPs added" isn't how I'd call it. More like BECAUSE. The base game was actually pretty stable, but every major patch and EP added something broken, or broke something existing. EA and QA... amirite?

Honestly, it's only worth playing because of mods which fix all that crap. But with the mods, it IS worth playing IMHO.