My house is a 1960s CA ranch with 8 ft ceilings. I have no baseboards. I have door casings that are original to the house which are plain, white and
2 1/4" in width. When I installed new vinyl windows a couple of years ago, the window company put trim around a large sliding glass door and 3 large windows in the same part of the house as the sliding door. This door and window casings are colonial style which is 3 1/4" painted white.

There are several doors throughout the house that cannot fit a wider casing than 2 1/4" (do to spacing issues). All of these doors are in another part of the house than where the new, wider trim is and these windows have no trim. So my question is: can you use different width casings on different doors? Could I put 2 1/4" new trim on these door in the same style as the 3 1/4" that is in the other part of the house?

Also, what size baseboard should I use? 3 1/4" to match the size of the newer trim but be larger than the trim around most of the doors? Or 4 1/4" so the baseboards are larger than all the trim (and double the size of most of the doors)

I know "can" do whatever I want, but from a design/remodel perspective, what looks best, is customary, and will allow for the house to look complete? My style is more in the contemporary, clean line look.

Thanks for any feedback. Also, I wasn't sure which section to post this in so hope I picked right.