Just adding some constructive criticism. Please make a balsa wood replica of your frame before you start cutting any metal. It will teach you a lot when you put some sort of load onto the actual car.
Also you will want to add some triangulation to your side impact "structure" as you have two hard points going into the center of the angled tube which means that angled tube is going to fold like a cheap suit if any sort of force is put on it.
Luckily, the suspension is pretty much done for you so the hard part is out of the way and you are just trying to connect the dots.
Good luck and have fun, but most importantly be safe!