I don't think a guitar can be too good !

If you wipe your finger board down when you are finished and once every two months (every one or two string changes) you should be Ok. You could try rubbing the finger board down with a rag that has had a small amount of lemon oil applied to it. This will both clean and condition. had will help soften and get rig of all that nasty gunk that accumulates round the frets.

When I say small I mean small as you don't want to drench the wood. To apply the lemon oil, put a pin hole in the foil covering the top of the oil bottle and apply one or two drips to do the entire finger board.

(Don't use this stuff on light woods)