I was thinking of using live oak as my material for my first shamisen. It has a hardness janka of about 2600 so I assume it is hard enough, just worried about the coarse grain for the neck.
Also is other any preference for quarter sawn vs flat saw for any of the parts?
I remember asking a luthier once why Oak woods aren’t used for guitars (I was asking about solid body instruments), and he said it was because it’s porosity is random and spread out. There are bands of hollow cells that flow through the very dense part of the wood, and that can create problems with moisture and acid and even laquer being absorbed into those porous cells, which can cause it to distort over time (not so bad for bodies, but can be problematic for necks). Also, it’s density makes it not such a good candidate for tonewood since it’s so bright, but for a shamisen, who knows if that might be desirable. And also, its heavy. You’d have to make the dou out of something comparable to keep it from being top heavy, but that adds weight to the whole instrument. So if you don’t like Les Pauls for their weight, you might not like an oak shamisen. 
Live oak is a bit different than most oaks used in woodwork in that it is diffuse porous so the porosity is more even though its density is even higher. I was actually thinking of making the dou out of it as well, but only voiced concern about the neck because it seemed like the bigger issue.
Just trying to think of wood I could locally harvest for the wood since I have a saw mill. I have plenty of acacia, mesquite, and some pistachio currently, pecan, hickory, and walnut are pretty easy to get in my area as well. Any advice on which ones would be good? Only instruments I have ever made are whistles and flutes, though I do play the violin I haven’t gotten around to making one yet, thought this would be a good warm up.
Mesquite wood can look quite exquisite, but from what I understand, it’s hard to find in long, thick pieces because of how the tree grows (I’m from Texas, and I haven’t seen a lot of straight mesquite trees).
One thing you could consider is making your sao like the Eclipse or the one Kyle Abbot is making (see his instagram feed. I think you might enjoy the progress pics he’s posting instagram.com/bachidoofficial). Anyways, the neck of these shamisen is two types of wood, one piece is the main part of the sao, and then another type of wood is used for a ‘fingerboard’. It looks fantastic, in my opinion.
I’m in central TX and it’s not too difficult to find large mesquite logs that are straight. They had trucks of them they were taking out of a ranch that was being cleared.
I definitely like the two tone, hadn’t thought about doing it though I am definitely going to.