Wow i love the name koven!!! Iv never heard of it but read it like a long 'o'
Its Koven with a long O :)
I like Koven Gage if it is pronounced with the long "o" (i.e., rhyming with "woven"). It might get confused with "Cogan" sometimes, but so what. If Koven is pronounced like coven, (i.e., rhyming with "oven,") he might get a bit of teasing about that. But only by people smart enough to know what a coven is, and that won't be many. lol If you are using the second pronunciation, (i.e., rhyming with "oven,") you might think of something closely related that is not quite such a soundalike to coven if you live in an area of the country where Christians are creeped out by the idea of covens.