Suggestion to improve game lag and save file size to some extent

Also, I was reading a post by someone and they mentioned something about books. BOOKS are another part of the huge problem. Per Household, I always buy all books available and collect them as my sims do read. That equals up to LOADS AND LOADS or books . I guess. I know we load into other households but I don't know if they are somewhat preloaded and I feel they are otherwise my game lag wouldn't get progressively worse when not really adding more items to my main households. Ok I am done. You get the picture.