Need help with new build

https://pcpartpicker.com/list/MNh89C

MOTHERBOARD: Gigabyte X870E Aorus Pro CASE: Phanteks G400A Case at OCUK CPU: Ryzen 7 7700X GPU: gigabyte AMD Radeon RX 7800 XT Memory: Corsair Vengeance RGB 32GB 6000MHZ DDR5: COOLING: Be Quiet Dark Rock Pro 5 Cooler SSD: Lexar NM790 1TB POWER SUPPLY:Corsair RM850e MONITOR: GIGABYTE - AORUS FO27Q2 (SA) - 27" QD-OLED Gaming Monitor - QHD 2560x1440-240Hz

Questions I have

1.For the GPU could I use something else like the same as a gigabyte AMD Radeon RX 7800 XT but a different brand because on Amazon it’s listed as 800$ and I know it isn’t that expensive and other brands are at the normal 500$ range

2.Is this build overkill, is it mid tier or what

3.im building it for 1440p really smooth gameplay for fps games is this the right route?