Polishing the internals might make it smoother to pump. It will still be as stiff, because you have to close the sear on the bolt against the main spring no matter what you do.
As for hitman mods, if you're a dab hand in DIY you could dremel a new frame with a guide rod or bolt a guide rod onto the front of your existing one. You basically need two guides (barrel and guide rod) to stop the handle from catching on one end.
You could buy another trracer and make a nasty trracer (two trracers bolted together). That's my next project