AMD is always an okay choice for a budget build, no problem there. I think you'd be happy switching to a more powerful GPU like you mentioned Its always nice getting to max or nearly max out the graphics and not having to tinker for the best graphics to FPS ratio.

As for mech keyboards, go to Massdrop.com and pick one up there. They're all awesome and you can get them (usually) well under normal prices. Not to mention you can choose your switches which is great.

And I have to recommend the Asus PB278Q for a monitor. It has good color fidelity and can be overclocked to 85Hz for some sweet looking gaming!

*Almost forgot mice. I have the Logitech G502 and Corsair M65, they're both sturdy, hefty mice that have a reasonable amount of customization. It's basically choosing which brand you like most.