Slightly difference perspective, but given that my wife and I are both ex-JWs it really does give a bit of an extra bond to know what each other is going through. We are shunned by both our parents so we can really empathize with each other on how it makes us feel. Also the little JW catch phrases can be a subtle shared jokes. The comment "from house to house and door to door" would really mean nothing to someone that's never been exposed to the witnesses, but it can earn a familiar smile when used in a why the WT would never approve.
In all, I'd say that there is potential, but our marriage isn't based on the fact that we are both ex-witnesses. It's accentuated by it. I'd say find someone that makes you happy, if they are an ex-witness then you have a common bond, if not, hopefully you have other things in common.