First addon: You could check out one of my earliest attempts at writing an addon called
OnScreen. Unfortunately, it's outdated, and it's a little messy, but I just looked at my old code, and it should still work. You would basically want to go into the options and set Minimap to "Show", but keep the "Enabled" button unchecked. Then go into key bindings, and set a button to let you toggle it manually.
Second addon: I use
Ellipsis for my cooldown monitoring, and I love it. You would have to manually blacklist all your abilities that depend on runes to prevent them from spamming you, but the process is very easy and you can do it right on the bar, without having to go into config screens or anything. Once you've spent 15 seconds doing that for all your rune abilities, I think it should about do what you're looking for.
Sorry if neither of these is ideal, but that's my two cents. Good luck!