I am not trying to get you to keep your money, but just today I watched an old Jake Kaminski video on plunger set ups.
For what it is worth - and this is coming from a 2x Olympic silver medalist - adjusting his plunger is almost the last thing that he ever does to alter his arrow's path. He does other actions first so that may give you a hint at what some of the world's best shooters do with their plunger. He may be an anomaly, but regardless it put plungers into perspective for me and I own some.
On my BB warf riser I have a Bear Weatherest with a hole punched into it so I could thread a plastic screw into the berger hole to adjust my centershot. I have fuzzy velcro all over the place on that bow because it is only a deer rib poke'n machine and not many people ever get to see it so who cares what it looks like! This is certainly not what you are looking for because it isn't shiny and NEVER needs me to mess with it, but it is an option that you get to tinker with once.
If you want a shiny object, consider a springy rest. I have one on a different riser and those are very good (albeit, not a fiddle'n with device, but good in other ways). I have a Dalaa riser coming to me and I may put that springy rest on it, like you I was considering a magnetic rest with a plunger but I don't like having even shorty plungers hanging off the side of my bow, especially if you like to use a bow quiver. A (Martin) spring rest will also stick out about as far as a plunger, that is until I whack it off so it only sticks out about 1/4" and grind a flat groove into it so I can adjust it with a coin if needed.