But it is quite normal that discussions go this way, isn't it? I think when we look at the teams one after another and compare their current accomplishments and consistent they are playing, it is normal to think that Leverkusen and Liverpool are the big favorites in this competition. But after all I think that everyone is aware we are talking about a knockout competition and in a knockout competition, everything is possible. Especially in a final where it is just one game, any result is conceivable. Nobody expected Sevilla to win the Europa League last season and back when Chelsea won against Manchester City in a the Champions League final, I can't remember anyone predicting that this would happen. For as long as Roma is around, their chances are not zero! 
Sevilla's successes in the EL are not uncommon, I agree that it was a little unexpected, but they simply repeated it again, something they have done many times. When Chelsea beat City I was disappointed, but you are right again, the final is just one game in which anything can happen. Now the final between Liverpool and Bayer looks just logical, everyone would like to watch this confrontation, but this is the playoffs, and a surprise can happen in any match, and besides, it seems to me that there are no weak teams left in the quarterfinals. There are a lot of adjectives in your post that I strongly disagree with. First of all, it wasn't "a little" unexpected that Sevilla was going to win that title again. It was completely unexpected and I can't recall anyone saying that Sevilla could win the title when it was still the group stage or the round of 16. Nobody really mentioned Sevilla once.
Secondly, you say that they "simply" repeated it as if it was no big deal for them to win that title. I am not sure what you base that assumption on, but it was not a simple title for them nor was it a simple repetition of what they accomplished in the years before.
The final between Liverpool and Leverkusen only looks logical if the drawings don't throw a spanner in the works and they play against each other in an earlier round. Two requirements: they both have to win the next round and they can't meet in the rounds before the final. I hope for that to become true, but no way to predict that final exactly for those two reasons.