Seriously, please help me formulate a good set of steps the average player can follow.
It's kind of tough to say, but I'll tell you my thoughts.
I agree with DP in that I don't report anyone for having a good game against me in the 1-hole coin rooms. Anything can happen there. I've seen Hacks and Amateurs make 25-50 foot putts against me. Didn't think anything of it. Anyone can get lucky.
I don't play Showdowns, but it sounds like you (DuFuss) are pretty good at spotting and reporting anomalies there.
Regarding other cheats, the only ones I really pay attention to are multi's. Not naming any names, but I'll give you 2 examples.
One was a series of 4-5 accounts where it was obvious to me that they were all owned (and being played) by the same person. They moved as a pack from CC to CC, sometimes starting (and closing) their own CC. I spotted them by their posts in the Forums. Always the same posting style (their posts were always in bold italics), grammar, and tone. Occasionally, whoever owned the accounts would post something using Account A, someone would respond, and their next response would come from Account B using the same "I" pronoun. Dead giveaway. I made a list of they accounts and sent it to WGT Member Services. They did nothing.
Another was 2 accounts, one a Legend and one a Pro. Same country flag and almost the same avatar (a big block letter). The Legend had gifted the Pro all of his equipment. The Pro was shooting 29s in the weekly SP tournaments with it, despite having only joined WGT a week before. The Pro came into one of our Discord servers one night wanting to play challenge matches against lower-tiered players for credits. He was investigated by the Discord community, outed, and removed from the Discord server. I (and probably others) reported those accounts to WGT. WGT, from what I can tell, suspended both accounts. Neither comes up in a name search and neither has been played since last September.