You can really do a lot with less than one would expect, depending on how you approach it.
I've gotten some great results by doing the line work as pencil, then scan, then some digital color.
That's not too intensive.

That said, if you want to do huge maps with tons of detail, labels, and all the frills, bigger is better.
My work computer is a few years old at this point. Trying to recall the specs...
I built this one back in 2015? 2016? I don't recall exactly.

i7-5820 [@3.30GHz] I generally don't overclock. Stability is better.
GSkill32Gb of DDR4 ram, gigabyte x99-ud3p mobo [always had good fortune with Gigabyte]
PNY nvidia gtx 960 4gb
samsung 500GB ssd [other drives including a 60GB ssd scratch drive for PS and other apps]
27 in Dell 2715H [not the most accurate color. Need to get a better 2nd monitor]
Wacom cintiq 27
win7 pro 64 bit
a solid silverstone 700w psu [stability is important]
I also made the leap to a liquid cooled system
I think it was a cooler master system. I can check if needed.
AND a battery backup unit. That is crucial important.
We have random power outages around here.

I found a decent large format scanner/printer and that has been an immense help with my work.
Epson workforce wf7520. Large format scanners are super expensive so this was a steal in comparison.
And large format printing was a good thing too.

Good audio was important too, as I am at this pc for most of the day.
So I got a nice set of M-audio AV40 active powered speakers.

For software, I try all sorts of things out.
I've had a number of versions of PS over the years. CS5 was the latest.
I'm sure I'd like new features, but I am opposed to monthly schemes.
I've found other useful software to be ...
irfanview - free image viewer with some features
other utilities... snag-it, PureRef, G.Projector

Mischief - a weird vector app, but has an infinite canvas, which is cool.
Krita, Sketchbook Pro, Medibang Paint, Inkscape, Painter,
Old versions of SketchUp pro, would like new version but once it was bought by Trimble, they wouldn't give me a fair upgrade price.
Old versions of Vue Infinite, would love a new version but it is insane expensive.
Paintstorm Studio - I'm trying more in this app. It;s nice.
Manga Studio [now clip paint] it's also very useful
I'm slowly trying to learn wilbur and Fractal terrains, but have less free time for that atm.

All of that software is because i have some unsolved issues with conflicts and errors somewhere between Adobe and Wacom.
The problems don't occur in any other software, just PS. But Adobe says it is wacom. shakes head.
I went ahead and got Affinity Photo and Designer to mess around with.
[geez, I talk too much ]