Beta / Alpha access will be available through PC/Steam, but you will be able choose any of the supported platforms which you want the final game key for. Beta / Alpha keys and the final game key are separate.
So if you are primarily a console player but also have a PC (the game runs even on most laptops), you have a chance to shape the game in Alpha / Beta and still get the final game on PS4 / Xbox One.
Yes, you can give any name within reason (no naughty words :). Your name then goes into a pool that is used to select a random name when a shopkeeper or traveling merchant is encountered by players in the game. We will contact you about the specifics after the project has been funded.
Due to the complexity of the game mechanics and the action based nature of the game it would be pretty hard to nail an ergonomic control method and that's why we are reluctant to move towards mobile. But if we come up with the proper controls then maybe a tablet version is doable.