As a hardcore BSD user, GPLv2 is perfectly fine with the BSDs. They all ship with GPLv2 software by default.

FreeBSD doesn't like GPLv3, but OpenBSD and DragonFlyBSD don't have a problem with it. I don't know about NetBSD off the top of my head.

IMO this seems like something that should be GPL and I think you needn't change it.