So, after looking through the teams league by league and seeing a variety of differences, I can now move onto more general splits – I should caveat this by mentioning that it only applies to Europe’s ‘Top Five’ leagues, a grouping which rather ignores Portugal’s Primeira Liga, which often represents well in the Europa League, and the Eredivisie, which is rather less forceful at UEFA level.
The first split that might make sense is the competition itself. If a team is in the Champions League, are they likely to struggle more than in the Europa League; certainly, the latter competition is blamed for a lot of teams’ poor form, and, well, looking at the graphs previously, it tended to be teams that were EL based who endured the worst disparity.
In short, no. Teams in the EL are poorer – but we already knew that – but both competitions have a slightly negative effect overall on the league games that follow their involvement. In both cases, that gap represents around 1/10 of a point and balances out at around 3 points a season.
On that basis, if you have an option of qualifying for either, it shouldn’t negatively affect your next season if you end up in the Europa League instead of the Champions League.