In addition to what you mentioned. There are also issues with building regulation as well.
The city should work with architects to develop models for housing types that are pre-approved. Such as four-plex that fit into single family neighborhoods. So developers can just pick those up and get building in a short period of time.
Maybe I'm late to the party, but I recently found out some cities are doing exactly that and I'd love to see it become extremely common. South Bend, IN is an example that has plans ready to be used of housing that is reasonably affordable to build. I'd love to see even more multi-family options, but let's not have perfect be the enemy of good.
In my city I'd love to have a catalogue of ADUs shapes and configurations I could just add by right.
https://southbendin.gov/wp-content/uploads/2023/06/SBBT_Cata...