Good luck in getting those odds. I don't see Vegas making a team that wins over 100 games this season, an underdog despite their records against each other.Of course there was a time when the team with the best record had a 50/50 chance of winning it all but with a playoff system everything is up for grabs.
While the Cubs have benefitted by the Wild Card in the past I'm not a big fan of the WC. There is something to be said for consistently winning over the span of a season. Perhaps they should just make the WC team play nothing but road games in the Divisional series.
As for this year, if I were a betting man I would bet the field against the Cubs because that is the safe bet. Also at least three of the teams that the Cubs could face in the playoffs have winning records again the Cubs this year so the Cubs should be underdogs against these teams.