Build Help Review - First Timer - Console Transition

Finally decided to try my hand at PC gaming after years of only using consoles. Would like to get some feedback.

I've researched the sidebar material over the past week or two and used pcpartpicker 's Entry Level Gaming Build as a starting point, and then made a few tweaks so that I could be at the recommended settings for the games I want to play. It started off at ~$572 on the original build and now it's at ~$900, but I also added a 24" monitor and Windows 10. I already have a keyboard+mouse.

What is your intended use for this build? The more details the better.

I'll mainly be using it to play some FPS games (Overwatch, Titanfall 2, Dishonored 2), and some strategy games (XCOM 2, Darkest Dungeon). It may be used from time to time for small things like web browsing, and editing some word docs too. In the future, if I end up enjoying PC gaming, I may do a completely new build in ~2 yrs and reformat this system to be used as an HTPC.

If gaming, what kind of performance are you looking for? (Screen resolution, framerate, game settings)

I'd like to aim for "average" framerate and resolution. I checked the recommended settings for the games I would like to play listed and the FPS games all seemed to point towards having 16 GB RAM and 8GB for Video. I'm not experienced enough to know if this is crucial though. No plans to overclock.

What is your budget (ballpark is okay)?

$800-$1000 (including Windows 10 software & 24" monitor)

In what country are you purchasing your parts?

USA

My main concerns are:

1) CPU - Could I see any performance issues here?

2) Power Supply - Is it enough wattage space at 450W (Current Build estimated at 390W)?

3) Fan cooler - Is it really necessary?

Build: