My suggestion? Skip the fancy board and spend a few bucks on a sturdy bench scraper, instead.
I don't think I'd ever use an un-sealed wood surface to roll or knead dough on. Too much friction. And 18" in either direction is kind of small for rolling or kneading dough.
Pastry likes to stay as cold as possible. I wouldn't mind having a marble counter top for pastry, but that's just a crazy fantasy that I would never spend money on, unless I found a nice, good-sized slab of marble at a thrift or building-materials reclamation store for dirt cheap.
Bread dough is less fussy. It does't make much difference.
In both instances, you're going to be flouring whatever surface you are forming the dough on.
I'm not sure why you would need to think about a surface for tortillas. If you don't have the skill to form them between your hands and don't have a press, you're going to want to roll them out between sheets of waxed paper.
Frankly, I've always either used a wood kitchen table top or a Formica counter top--whichever I have better access to. In restaurants, stainless steel is the norm. As I've gotten older, I prefer the counter top--easier on the back--that's more important than the surface material. I've always rolled pastry dough between sheets of waxed or parchment paper. I also form pizza crust on a sheet of parchment, so I can slide the sheet with the dough on it onto the baking sheet without damaging it.
For cleaning up, It's easier to use a bench scraper and then wash down the Formica, IMHO. If you are concerned about the counter having been used for other things, spray it down with a bleach or peroxide solution, then rinse thoroughly before proceeding.