I think even a single ride can be a tremendous draw, even if not attached to a family fun center or other sort of attractions area. I'd love to see coasters get built that are an attraction within themselves - I know that England has a few like that, not attached to parks. Granted the ride would be expensive to build, but especially if it is an area removed from large parks, it would pay for itself very quickly.
I like the idea too, being able to ride some rides/coasters without spending the whole day or paying the high admission price. I'd be more than willing to pay-per-ride if it's just a way to let off steam after a long day. Lead me to it! :)
(Hoping some city officials from Jacksonville, FL are reading this post!) ;)
-------------
Po!nt of View: A different look at Roller Coasters.
http://www.crosswinds.net/~justmayntz/thrills/index.html