I just want to add a note here about street plans. This may be a personal quirk of mine that doesn't bother anyone else (I have an... unusual mind with none of those little boxes in it), but I tried adding a street system first and then found myself deleting most of them because they were getting in the way of the more elaborate buildings I was designing.

Basically, a street layout helps with the major roads, but the smaller ones may need to be more organic - an integrated part of building the houses... or whatever.

I hope that makes sense and is in some way helpful in the future?