Really, you can't overskim. Kind of like you can't really have too much light.
I would have to disagree. I mean if there is no budget, I guess you can get the most expensive/high performance skimmer for your tank. But ultimately you would get something practical and for the size of the tank.
But keep in mind foam fractionating does not pick and choose what nutrients it brings up to the skim cup.
As for having too much light, with some of the hobbies current lighting methods, light comes with heat... Bleaching of corals can occur and light in combination with poor parameters can cause unwanted algae. If one cannot have too much light, why not run lights 24/7 (taking out the account of the electricity bill)?