I haven’t played any of the Witcher games myself (not my sort of thing) but I checked out the soundtrack after getting a tab and it’s very much my sort of thing. I immediately picked up on Gwent Flute Song as being a good candidate for a ukuleling. It’s a fun pastiche of traditional Irish music which always sounds great played campanella style.
Unlike traditional tunes, which usually have two or three distinct sections that you switch between, Gwent Flute Song has a number of variations around a central theme. That means you’re using the same shapes throughout the tune but with subtle variations. That was a killer for me to memorize. If you want to cut down on the variation for your own version then go for it. I did that a bit myself. In my version bars 36 and 37 are the same as bars 40 and 41. Which isn’t the case in the original.
For most of picking in the piece I use thumb and two finger picking. But using my index on the C-string when it’s played next to the g-string e.g. bars 31 and 33.