There are plenty of gaming laptops in the £1k - £2k range that would suit your needs easily.
Basically a good entry level would be a
9750h / 1660ti GPU
Mid level
9750 / RTX 2060 GPU
Top end
9750 / RTX 2070 or 2080MQ
There if you want 'bulky' but slightly higher performing, or thin/light with slightly reduced performance, but more luggable.
I was all set to get something from the usual big brands, but I decided this time to use a UK company who build their laptops on the well reviewed CLEVO chassis. The beauty here is you can pretty much spec things how you want, choices of CPU/GPU/RAM/SSD/M.2 and even screens in some cases, so you can get what you want for most budgets.
I recently picked up what is Clevo P960, 16.1" (Very thin/light gaming laptop), just spec'ing that to give you a very top end gaming laptop experience based on your requirements:
- 144Hz Display (bright 300+ nits display)
- Intel 8750h (6c/12t) or can get the 9750h for £140 more
- NVidia RTX2080MQ GPU - 8GB GDDR6
- 16GB DDR2400 RAM
- 480Gb SSD
- 1TB Intel M.2 NVME
£1830 (£1968 if you want the 9750h)
The main brands are charging £2900-£3200 for something similar.
The Clevo P960 is used by several custom laptop builders, but essentially all are the same, here are a couple of reviews that swayed me:
https://www.youtube.com/watch?v=XzuBuPQyGE8
https://www.youtube.com/watch?v=Yvh79BMSNa8
You can get the 17" version (p970) for the same price, heres a review of another resellers
https://www.youtube.com/watch?v=6I2znkggA7U
I will say that for the money they are unbeatable, I bought mine without M.2 and extra RAM, I just bought that separately, it's easy to upgrade and now have 16GB 2666 RAM with 1 x 1TB M.2 Drives and even a 480GB SSD, so it absolutely flies when loading windows, gaming or doing video/photo editing.