@newcitysims For that price, you could get a better graphics card, or you could get the 1650 and save the £200+. While this laptop's processor is much better than the Ryzen 5 3550H in the Asus models, the processor isn't really the important factor here. Any of these CPUs would run Sims 4 just fine; the quality of the experience will be about the graphics card, and of course how much you enjoy looking at the screen.
As far as refresh rate goes, some people notice a difference between 60 Hz and higher, and some people don't. If you were curious, you could go to a store that has monitors on display and look at a few. The fastest test is to open a File Explorer window and drag it around the screen really quickly. If you don't notice a different between a 60 Hz and a 144 Hz screen then, you probably never will.
If you really want a 17" screen, there are fewer options. I linked the cheapest good one with a 1650, although it's even a bit cheaper on Amazon. The cheapest one with a 1660 ti is this £1,000 Asus. It has the weaker AMD processor (almost equal to the i5-9300H though), but on the other hand, it has 16 GB RAM. While memory is easily and cheaply upgradable, and doing so doesn't break the warranty, it's still convenient not to have to add it after purchase. It does look like this one has a 60 Hz screen though.
https://www.box.co.uk/FX705DU-H7083T-ASUS-FX705DU-H7083T_2839527.html
The same laptop with a higher refresh rate screen is £1,060:
https://www.laptopsdirect.co.uk/asus-ryzen-7-3750h-16gb-512gb-ssd-geforce-gtx-1660ti-6gb-17.3-inch-windows-fx705du-h7083t/version.asp
I saw a number of 17' laptops with a 1660 ti for £1,100 and up, but I didn't know whether you wanted to pay that much.