Well, if it were my build (and 2k- 2.5K'ish will be my limit) - a 2K limit to be spent predominantly MMO (assuming WoW) then a 3700X would sit well within the build and offset the 2080 Super's premium - and an 8c/16t CPU wouldn't look out of place in a 2K setup.
my 2p:
ryzen 3900x
gigabyte x570 aorus elite OR asus TUF gaming x570 plus (£210ish) OR asus tuf gaming x570 plus wifi (£240 - if you want wifi)
Crucial Ballistix Sport LT BLS2K16G4D32AESB 32 GB Kit (16 GB x 2) (£140)
Corsair RM750x 80 PLUS Gold (£80.51)
geforce 2080 super (~£675 when released this week?)
corsair mp 510 960gb (£130 inc shipping - check manufacturer site for details)
Scythe SCMG-5100 Mugen 5 Rev.B (£43 - ocuk)
Phanteks Eclipse P600S Silent Midi Tower Case - Black= £127.99
works out at around the same price as your spec above, but with:
better ram
bigger psu and cheaper
nearly as good cpu cooler at half the cost of the d15
monster GPU (2080 super) from the cost savings
can get a 2080 super with a 2k budget with a 3900x. which is my point i made exactly:
OP is spending £2000 on his new computer. that 2 grand can either include a 2070 super, or a 2080 super - with not much detriment to the other components.
clearly holistically, the 2080 super build is the better bang/buck rig.
unsure why everyone is saying 'just' get the weaker card. makes no sense whatsoever.
with that being said...OP seems to want to stick 100% with ocuk. so the above build isn't possible.