Just a thought, please bear with me and please feel free to add or correct this idea. It is only a quick thought on how to improve the game.
As we are aware, all cup competitions have a form of seeding involved.

So league first. Extend the leagues to 16 teams and during the first half of the season play 2 league matches on 4 diffent days so the season does not have to be extended.

Main cup competition - teams spread over 4 levels (say 10,11,12 and maybe 13). Preliminary and qualifying rounds between 10 and 11 max difference with the level 12 and 13 teams entering at play off stage. So there will be only 64 teams in preliminary, 32 go through to qualifying and then 16 join the 'big boys' in play offs. Then on to last 16 etc as normal.

For the second half of the season, play a league cup between the teams in a particular league only. This could revive players interest who have been knocked out of the 'main' cup early and no CL place and give them something to play for 2nd half of the season.