Hi,
Interesting suggestion. I doubt it'll ever make it into the mod, though. The random nature of the oil fields going to make this real tricky, as well, I think people that want beacons, also want to get to most out of them, and P.U.M.P. just can't offer that.
There's a dependency on Module-Inserters mod, though. If you install that mod too, and configure it to add modules to pumps, P.U.M.P. will query that mod which modules to add to the pumps placed by P.U.M.P.
It's no beacons, but at least you get some aid for modules. I hope that'll do.
I do want to add powerpoles, though. It's going to be equally hard to do, but I see more gain from them. Who knows, maybe once those are in, I'll reconsider auto-adding beacons as well. :-)