West Coast of Florida

You mean peninsular Florida? Possibly Highway US27 or if you want to stay to the west(but not near the coast)then US19 but you won't hit many towns unless you divert down side roads to the west. It is not possible to drive down the west coast. 27 goes thru many small towns. It's actually hard to say since there are really 4 or 5 highways that pass south down the peninsula. 19, 27, 41, 301, 441 and maybe 17. They merge and run together for 50 miles then split up. If I had to pick one then maybe 41 it runs all the way down to the everglades and then along the northern boundary of the park, as the Tamiami Trail, into Miami. Lots of history behind the Tamiami Trail and many dead tourist and locals drove into that deep canal and were not found for decades.
Just get a map an look is probably the best advice.

Maybe we could come up with a list of small towns but it would be difficult.