As others have mentioned, I would suggest getting one just to try before going for a 4800$ macbook pro or a mini(was that the second system you mentioned?) The mini is up for a redesign, so there will be a smaller one coming out next year.
MacOS is very easy to use which is can be great but it can also be a con if you have been a heavy windows user for years. The two operating systems are very different. MacOS is Unix based, so if you have no familiarity with Unix/Linux, it can be very frustrating the first time you are met with a troubleshooting issue, or just trying to figure out the MacOS file structure.
For me one of the best parts of Apple is their ecosystem. If you have an Iphone, Ipad, Apple Watch, Airpods... they all just work together in harmony. For the most part
With Icloud, I know my desktop, documents, picture, notes, etc are all going to be in sync across all of my devices
Also you mentioned you have a gaming laptop. I have been a huge gamer most of my life and Macs are not known for their gaming ability. These new chips might change that, but if you still want to play AAA titles on your laptop, you may want to rethink going full Mac
I have the Ipad Pro 12.9 inch and I wouldnt get the smaller one for photo editing honestly. The screen is just too small.
If you are just wanting a Mac
JUST for photo editing, you may be disappointed overall. If you are a lightroom user for instance, you are not going to see a massive difference between running it on a Mac vs PC.