A hearty DITTO! to the idea of doing a first run on some cheap house building wood to work out the processes and motions first. It'll also allow you to iron out things like the size of the wrist and any pistol grip sizing and spacing along with setting the cheek height to suit your sights or scope use. For a one off which has to be right the first time around it's well worth the time and the $3 worth of wood.
I've done a bit of work with zebrawood and it's not that soft at all. I'd class it in the same range as a softer walnut but not quite as hard as black walnut that I've worked with. So perhaps a little more area for a recoil lug to sit against or possibly an inletted hard maple pad for the recoil lug to seat against. But if you like the look of zebrawood it's more than usable.
Maple is far too heavy for a carry around gun unless you make it quite slender. Oak is tough but heavy and can often be rather brittle. As in if you accidentally drop it and even if it's in a sleeve it might just shatter at the wrist sort of brittle depending on how deeply the wrist is shaped. Mahogany, the real stuff and not the luan from the Phillipines, is pretty good but the grain tends to be rather "meh.... " in some cases. But if you can get it with a nice ribbon texture it CAN look positively electrified when the light hits from various angles. But if you find such a piece it's a bugger to cut with anything but rasps, files, scrapers or sandpaper. Any use of planes or spokeshaves will produce lots of tear out since each ribbon band has the grain running at a different angle so NO direction is good for planes. It also responds best to sharp scrappers for the final finish to best bring out the brilliance in the ribbon pattern. Using most sandpapers on it results in greatly dulling the magic down.
i looked into zebrawood! its gorgeous! but when i went and found some, i like it!! i was talking to the guy at windsor plywood today and hes got me looking into bubinga and paduk. both exotic african woods, and they are beautiful!! i just out if they can take the recoil. its for a 243 so im not terribly worried. the mahogany they had was pretty meh.. so ill probably end up not going with that.
its going to be a heavy gun no matter what. its a heavy barrel. im not to concerned about the carry weight either; all my rifles are heavy and i carry them around (remington sendero and a vls)