Manchester united has the qualities of winning the europa league but it is not still certain becoming the champion of the league will go to them. Anything can happen along the line, football can not be predicted and their other good teams that are good to win the europa league too.
There are some strong clubs that played in the europa league as well. I think that your focus must not always be on united. United was most favorites club for now but i think that if you need also try to consider about some important clubs like juventus, arsenal and many more.
In my opinion if any team that played in the europa league have the same chance. Juventus has not yet faced a strong team like juventus. roma, leverkusen, sevilla. I think that these team are underrated team at this moment in europa league.
The fact that if MU has become the most favorite team but let's see how it will be going on when MU meets juventus. That's gonna be a tough game for MU. Beating barcelona didn't mean if MU will take trophy easily.