Unless I've overlooked, but I don't see any domestic cup competitions between club teams of the same country. It'd be cool to have such a tournament that somewhat mirrors the UEFA Champions League but, instead of having one group stage in the tournament proper, start with maybe two group stages depends on the number of teams, with the bottommost tier teams play first and higher-tier teams gradually join in subsequent knockout rounds (either single knockout of best-of-3). The tournament can last as long as needed within a season with games on non-league matches dates.
If there's such a domestic tournament, especially for the senior leagues, please direct me to the info page. Otherwise, please comment whether this is feasible or that I'm out of my mind.
Thanks!