The Oilers should beat the Hawks, but in a best of five series, anything can happen, especially in favour of the team with superior goaltending (Chicago). Still, I don't love Chicago's run & gun style, and possibly the league's worst 5v5 defense, going up against two of the league's very best attacking forwards. Tippett has built a somewhat crude, but effective system that won't make it easy for the Hawks to score at will. Still, a shorter series definitely helps Chicago's case.
After that play-in though...I can't say I love Edmonton's chances. With McDavid plus the new dynamite 2nd line, they of course could win 4 games against any team, but I wouldn't bet on them to be the favourites in the West ahead of much more well built, deep, and balanced teams like St. Louis, Colorado, Dallas, & Vegas.