GALs are reprogrammable unlike PALs, so treat this as a firmware update. Downloading the fuse map into such IC is an insignicant effort. Redisigning the equations is the smarter thing to do, especially if it can save your buffer. Is there a proof the rumored problems were due to the lack of that WE signal buffering? It may not only be buffer loading capability that could be beneficial, it may be the delay it introduces.