If you do remove much surface depth, make sure you don't take off so much that tee nuts bottom out on parts and accessories when tightened. Also, of course that the surface you leave is as true to the slides and ways, or truer, than you started with. A cosmetic cure can sometimes become a functional issue for a whole lot of different reasons. A buyer who is aware of cosmetic problems won't be upset with the purchase if it's reasonably accurate for its age. One who buys a freshly machined table that is inaccurate will feel resentment. Not saying don't do it, just think about it.
Rust can be removed by the electrolytic process with washing soda and a battery charger using a plastic dustbin.I've even done it in situ with cloth pads dampened with solution and a plate for an electrode over. It's amazing what that can do to an ugly machine surface. It can look new in sheen, and any divots filled with plugs or epoxy filler so everything looks ship shape and well managed, just not perfect.