oh i didnt see you said 1000 pounds,i thought dollars.That leaves us with 200$ more to work with
Check this out:
https://pcpartpicker.com/list/RsgRXv
you have to use the website
https://uk.pcpartpicker.com
for accurate builds since price and availability of components varies around the world.
And from what I can tell, things are quite a bit more expensive in the UK for parts.
You can't just look at components available in the US, and simply do an exchange rate for USD to Pounds and call it a day.
Also, a problem with your build is that you put two kits together for RAM and that's a no no.
While they may possibly work together, it is not guaranteed, and you don't want to risk them not working well together and so it is better to just buy RAM in full kits.
Also, also, 32GB of RAM is a bit much for gaming. 16GB is still plenty.
Another also is the RTX 2070.
The 5700 XT performance is on par with a 2070 super and for cheaper than the 2070.
If the user in question was going to take advantage of any particular feature that only comes with NVIDIA, then I understand choosing NVIDIA, but their budget unfortunately doesn't allow for silly things like RTX On, and they didn't say anything about streaming so I don't think they are going to want one in order to use NVENC encoding, so for the price, the AMD card is a much better choice for the 1k budget.
The case you picked, while fancy looking, doesn't have much room inside for building in, and has poor airflow, and comes with only 1 fan I think.
Don't take this the wrong way, not trying to put you down, just making observations about things that don't make sense to help you improve on building knowledge as many others did for me at one point in time.