Congrats and welcome to the madness. Regarding string lengths, buy some C9 Socket line and bulbs and build the perfect application for each section. Tag/label them and each year it is a simple installation. There are some companies out there that sell lighting strips that you could mount around the framing (or to it) and then just clip the lights in. With the limited space that you have, you may want to consider multiple strings of different color lighting for the roof line, firesticks for vertical movement with controllers, mini trees in yard (few on each side, and/or arches along the driveway and sidewalk.
As to surrounding neighbors, they will come around next year with a little more to keep up. We went animated last year and this year many of my neighbors throughout the community have increased their personal displays and I hear it from the families each night when viewing ours.
My best advice is to set a plan for style and color. About 5yrs ago I made the commitment to upgrade to much better quality products and stop buying from the box stores. In doing so, I chose my three color style (R, W, G) and then purchased from authorized vendors when running sales.