Build Mode Ideas

I'd really like to be able to toggle foundations on and off for different on the same lot. For example, using foundations on decks, pools, and patios without having to have foundations on the house itself. I'll add my vote for different stairs as well, as having only the one type is frustrating, especially when the space for placing the stairs is small. I wish spiral stairs would make a comeback :( The final thing I really wish for is either a ladder or something akin to it to use for a tree house :( I want to build tree houses for my Sim kids but I really hate using the currently available stairs as they don't look right and take up so much room :(