I'm experimenting with road placement in terms of traffic flow:

I took lots of pictures to show the progress of each zone placement and road extension

The First development:

After some time, no more houses came in, so I laid out where the next pod of residential would be.

I figured I would have more success if I knew where the residential would go and then I could just base the commercial along the main roads

To the right of the zoned residential, I planned for all commercial, but it didn't look good, so I took it out and made a smaller area

To keep the areas separated, I added parks and plazas. I don't like the result, and I doubt I'd do that in the future, it looks weird.

The other area would be on the other side of the main road. I thought ping ponging back and forth over this main road would lead to even development. But I didn't want to do square swirl residential for all the pods, so I made a terrible shape instead

Commercial demand started to taper off, so I held off on zoning along the main road to the left of the new residential area above.

Not sure what I wanted to do next, so I killed time and planted tons of different trees. Not realistic by any means, but I'm not worried about that

I began to put in a sea port and harbor stuff....

and the game crashed.......

but I got something out of this:

Create residential pods off main roads, with 2 -3 connections to that main road.