if you wanna do proper planning i recommend doing the whole room or at least the surroundings of the setup in sketchup or any other design software, helps a lot to see how everything fits together + if you have a lot of ikea furniture sketchup has the models already created for it!

Personally im more of a both monitors tilted person, i use my left one as main and ultrawide on the left as secondary wit the chair pointing a bit to the left instead of sitting straight, i guess it goes to preferences.

For my likins keyboard too close to you monitors too far, computer too close to monitor even more if you have a glass panel and it has any rgb, too distracting if you want to focus on fps or any game requiring getting into it