Primarily you wanna go with it for the feel, I like the hardness of maple boards personally for bass, guitar I'm not really too bothered and if anything have slightly more preference for rosewood/ebony, but I do feel that maple boards do add a tiny little bit of snap to a bass tone which I quite like.
Maple isn't as hard as Ebony or Rosewood. Tone not only depends on the individual piece but also on the rest of the instrument and a host of other variables not being considered here.

