I just ran a quick search on your gallery. William Coye's work is so varied, it's a little hard to pin down any one trait.

I think it's because Coye had a lot of different influences. As a teen living in Bristol, RI, he first took instruction from Stephen Hartshorne. As a married man living in Plymouth, MA, Lemuel Savery was his brother in law, and he also worked alongside Amaziah Harlow Jr. and his own protege, Nathaniel Holmes.
Many of these men did collaborations on each other's commissions. E.g. Holmes did some of Coye's inscriptions, and Coye did lettering on others.

Here, Hartshorne and Savery seem to have been who he was emulating.

That makes perfect sense. Only two things are certain in life: death and taxes. In the mid to late 18^th Century, there would certainly be enough work to keep a number of stone carvers busy, sometimes simultaneously.