My opinnion is that lets make divisions. DIV 1 has 16 teams.. They play 4 times against each others in regular season. best 6 teams goes to straight to playoffs. 7,8,9,10 plays pittyplayoffs 7vs10 and 8vs9. Best of two serie. Winners goes to playoffs too.. So there will be 8 teams in playoffs. Playoffs: best of seven game serie.
Division 1 worst ranked team will relegate automatically. And the second worst will play against div.2 second best team.
Division.2 Has also 16 teams and same season and playoffs system like DIV.1 Winner will promote automatically. And the second play against div.1 second worst ranked team game seven playoff serie. Winner will play next season in div.1.The worst 3 ranked teams has to play relegation group game to stay in div.2.
Division 3 can have a 4 groups same much teams like last ECL. Every group best ranked 8 teams goes to playoffs. so its 32 teams same playoff system like the last season in ECL. Finalist goest to promoting group games.. and the semifinalist losers play against each others "bronze game", and the bronze game winner goes also the promoting group games.
So the div.3 best three ranked and div.2 three worst ranked teams will play own season. They play two times against each others and the group best 3 ranked teams will play next season in div.2.
Only problem is that div.1 and div.2 regular seasons has to last longer than div.3 because div.3 teams has much more. So the season will end same time each divisions. So they can play relegate/promoting match before divisions start a new season with the promoting/relegation teams.
It would be also nice that team will get marked on their website what they have won each season. Like "Champion of division 3, 2014", Champion of division 2,2015", Relegated division 1, 2016"..etc.
Its just my opinnion