Tolland County has quite a bit of terrian features that the system they have now works as best as it can for them. Some of the links or repeaters are fire department owned, some are TN owned and have various capabilites. I know they looked into a different radio system but the cost of it would be overwhelming to the towns that uses TN.
Basically, way too expensive to cover the areas needed and those towns cannot afford to spend the little money they have to cover the costs (as far as trunking goes). Last I heard there was talk in putting in regional (to the county) simulcats repeaters (still $$$) for wide area operations, but with so many departments and lack of some radio discipline, it would be a logistical nightmare.
An example would be the usual summer storms causing multiple alarms in multiple fire districts with everyone loading up the main dispatch/operations channel. Not a good thing. This is why many of those departments use their own fireground lowband or uhf channels.
Would be nice, but funding just isn't there.