I own the same boat and it surfs very well. It's no tourney surf boat by any means, but will do great for most any surfer. You can add ballast, that's not a problem. We surf with stock port and belly full, 400 lb sac in the locker on top of the stock rear tank, another 400 lb sac in the transom walk through and a 300 lb sac in the bow on the port side. Any people on top of this just makes it that much better. I am going to get a 750 for the walk through and get one of the long skinny 300 lb fly high sacs for the long storage compartment that runs along the port side. At that point it will be a real nice wave.
You are right, it's not a pro surf boat but I would not have any hesitations about being able to surf And surf good behind it. I don't have any great pics or I would post them. Maybe I'll get some this next weekend.