Of course Liverpool and Bayer Leverkusen are the main candidates for the title this season. But Milan can probably do well too, they played well in the qualifiers. I also like Sporting Lisbon, who also did well. I think this Europa League season could easily be a surprise. It could happen that for example Bayer and Liverpool meet before the final.
There are many strong teams in the Europa League this season so there will definitely be interesting surprises before the final if they can all meet each other early. But for now I prefer Liverpool to become champions in the European League this season because the team has also proven itself in the Premier League so far where Liverpool is still at the top of the standings. However, if Leverkusen can succeed in the Europa League it won't be so bad because in the Bundesliga Leverkusen is also very good this season.