I said this before: I don't think that there will be any more increase in the item limit, EVER. That this is just another design challenge. I have found that whenever I redesign an area, that area uses less items. Sometimes by design, but mainly due to the fact that some of the new items take up more space. Because the new items are larger then what was there before.
I decided to redesign rather then do nothing. I waited two years for a SH expansion before I decided it wasn't going to happen. Another design challenge.
My prediction is that there will be no more land made available and the item limit will not increase. Just something to deal with.