Delta Wing Scratch build

[Vaeloron]

I am working on a full scratch build delta wing and was hoping to pick some brains. I know very little about airplane design so I am not sure on a few things. I will be building from balsa. I have done foam builds but foamies just look cheap and toyish no matter how well they are done. I am going to go with a basic equilateral triangle shape with a fixed vertical stab and elevon control. It will be a pusher and I would like to do an EDF but I am open to going with a pusher prop as well. My first question is will there be any problem with my basic shape of the equilateral triangle. Second question is will the lack of a functioning rudder make a difference when I mainly fly bank & yank anyway. Third question is regarding wing shape, I know I could actually get away with a perfectly flat wing but I understand they don't do well at high speeds. What would be the best airfoil shape? I will upload an image a little later that gives an idea of what I have in mind.