as specced, you can get a lot more value for money by dropping your requirements for corsair and sapphire. as you say, they aren't the cheapest and there's other brands that do the job for a lot less.
that saving will allow you to get a massively better GPU (rtx 2070). the reason for opting for a 2070 vs a vega 64 is that you sound unlikely to want to play with the settings, so out of the box, 2070 does a better job than vega 56/64.
not quite sure i follow that line of reasoning. 2700x doesn't draw
a lot more power than the 2700.
sure it draws more power than the 2700, but that's because the 2700x's out-of-box clocks are higher than the 2700.
2700 = 3.2ghz base clock, 4.1ghz boost clock
2700x = 3.7ghz base clock, 4.35ghz boost clock
if they're both overclocked, on average, they'll draw the same power (perhaps the 2700x slightly less, as it's in general a better binned chip!)
hence the reason why the 2700x makes more sense if not overclocking. just set the offset voltage to -0.05 to -0.1v and let PB2/XFR2/PBO do the rest.
also the 2700x has the better boxed cooler.