Looks great! I think to improve this further, you could add additional detailing to the buildings and roads as they’re quite simplistic at the moment. Perhaps some vines, plants, pipe systems, street lamps etc. In terms of building ideas, I can give you a couple essentials for a town:
Emergency department (Fire, Police, etc)
Food related structure (café, bakery)
I find it helpful to go to the internet for inspiration as well! Just looking through images can give you ideas on what to add if you ever get stuck.
Also forgot to mention, all the buildings looks the same, with just different heights. Try adding more different signs and change up the colours. You could also try adding those little stands on the black platforms loads of places have outside to advertise?