I'm not for the Europa league; it'll only add confusion. It's better to have CL only; Europa league means giving chance to the 10th place team in PL to qualify. That means 50% of a league gets in a CL/EL tournament. In PL, only 25% get chance in CL/EL. In TE, 29% get chance in CL alone, so undeserving teams shouldn't get another tournament. Other than that, some teams may deliberately try to finish 5-7 to avoid schedule cluttering.
The regional Cup is a good idea, but difficult to implement.
Only the U21 league is which I'm interested. I'd suggested it somewhere.