The angle it totally dependant on where you are in the world and at what point in Earth is in it's orbit, which is why the sun is lower in the winter than in the summer for example.
Quite frankly, the way I do it is put a sun sprite in the sky, set the entity order so it draws behind scenary. And the put it at entityx(camera)+xoffset, yoffset , entityz(camera)+zoffset then play with the offsets until it looks right.
With regards to putting an actual dx light somewhere, again, it's just play with it until it looks right, but for the visible flare you should use what I mentioned above or it'll look like it's not very far away (because it won't be!)
Quite frankly, the way I do it is put a sun sprite in the sky, set the entity order so it draws behind scenary. And the put it at entityx(camera)+xoffset, yoffset , entityz(camera)+zoffset then play with the offsets until it looks right.
With regards to putting an actual dx light somewhere, again, it's just play with it until it looks right, but for the visible flare you should use what I mentioned above or it'll look like it's not very far away (because it won't be!)