Its generally sold as santos rosewood in this country and i have used it a few times fro fretboards. I believe its now morecommonly used in the industry as a substitute for Indian rosewood and for all accounts its very similar except more a bit more brickish in colour
And everything affects tone - you just have to work out how much
The frets are directly coupled to the fretboard so when you fret a note most of the vibration is transferred to the body from two points. Firstly the bridge directly into the body but also through the fret into the fretboard into the neck and down to the body. The vibration of the body is important because it affects how the strings carry on vibrating... and thats why its not just the pickups that are important for getting the right tone... even on solid body guitars!!
Now if you take that into consideration the fretboard has to impact the tone. Personally i feel it has more of an impact on the attack of the note rather than the overall tone or sustain, although obviosuly they are all part of the same thing... i'm just saying i feel the fretboards most impacts on the intial tone of the note. Other people will disagree and i dont mind that
Ebony tends to have a sharper/brighter tone. Maple can also be bright but i dont find it as sharp in the initial attack. Rosewood has a softer attack with more warmth
Now since you have pretty much decided on hollowed mahogany with a maple neck i dont think you can go wrong with the fretboard wood. whichever sounds more like what you want
