I had a contractor that I used a handful of times just poor a curb that looked like it was poured by drunk. 

That's your choice.Then I'd talk to a Landscape Architect and have the person come up with some curb appeal ideas, and then get bids on that.If the total cost comes in below the per door cost to move forward then it "MIGHT BE" a go.I believe looking at each unit as one job to be completed is more intuitive than looking at the whole complex as a job to be completed. 

This can help with seeing how far off  an overall widening could occur.If your property is also where a curb cut yield or turn could be placed onto another road that could also impact the land. 

You have to get the land REAL CHEAP and make sure SITE COSTS can be kept to minimum to try and curb risk.If you pay a premium for the land where margins are slim and everything has to go right to turn a profit then the risk versus upside ratio is out of whack.I have been in the business about 15 years and I listen to those in the business over 40 years and own millions of sq ft. in properties.

That being said, my advice (so they have the strongest ROI) to clients is to provide a polished and pampered experience for guests, and beautify homes, both curb appeal + interior + yard/hangout spots.

This edict is really in place for self-help LLs, most of whom would be breaking the law anyway by changing the locks or putting all their stuff on the curb.  

Curb appeal and making the home seem less like a manufactured home will primarily be secondary concerns. 

My response is that people sometimes park next to red curbs, too...

You have to have a permit, and there are specifications for what the driveway, drainage, and curbs must look like.At our family house in MO, we again has a similar situation.

The assumption of your plan based on your notes is that: you're planning on subdividing the lots, creating a development agreement with the AHJ for the land, CC&Rs, any necessary utility/landscape/road/streetlight district annexations, building out the master development infrastructure (water, sewer, power, telecom, roads, curbs/gutters, sidewalks, landscape/stormwater detention, streetlights, fire hydrants, driveways, traffic signals, etc.) and then developing each individual lot.