For a noob in building your first rig and asking us how you did is one of two things. One you know how you did and want to show off your new rig for braging rights.
Two you are not quite sure that you made a mistake and want us to point it out. Well I fell it is both of these points. You did good for a noob and you didn't make a mistake.
That is one good entry level gaming rig. Good job and hat's off to you. Good luck and have fun gaming.