Would a pagefile on an NVME hinder it's lifespan as they're a bit more critical on lifespan compared to a HDD or even an SSD so I hear.
Ok so I decided to move my pagefile to my Intel NVME, and leave a bit on the samsung OS drive, removed totally from the HDD's and WOW, cities skylines whilst still crap frame rate doesn't freeze anymore, I used to have to zoom into the city, and move around for 5 mins to get it all loaded, this doesn't happen anymore!
This is because an SSD is the best place for page file due to random access.
You should also where possible span the page file over multiple SSD's, it gives a RAID 0 effect and speeds page file access even more.
This also shows that 16GB is not enough for your computer, and you would benefit from more RAM.
I definitely need more RAM for cities skylines, but can I justify 100 quid just for one game? Probably not.
Just to clarify are you booting from the SSHD? Also, do you have space on any of your SSD drives?
If the answer to both the above is yes, then with one of your SSD drives enable ReadyBoost via properties on one of your SSD's. 32GB is the max space that can be allocated per drive and you may as well use this amount if available.
There will be people now that say it won't work, but don't listen to them, enable the ReadyBoost and see how the computer feels afterwards.
I have one NVME on my desktop and 2 in my laptop
The NVME I'd boot drive and page file, it flys now!