I honestly looked into the shadows 30min before commiting, cause i felt the same, but my brain was to fried to get in anything less haha.
The strenght and weaknesses do have something todo with the color wheel.. but more the RGB one, so R>G>B, and then Yellow is half R and half G, Purple R/B and Cyan G/B. It might have been clearer using the actual color wheel...
Am glad to read you enjoyed it, it was the goal to get as much of the pokemon first genearation system in there :D