This is a minor point but if you change your Excadrill to have a Jolly Nature and Brick Break, then Excadrill should hold a Life Orb or it will do 70.7% to 83.4% to opposing Excadrill. With LO, Brick Break will do 91.7% to 108.3%. After SR that's about a 70% chance to KO, as opposed to 6% if you have Air Balloon (of course, these calcs include the chance for a critical hit). You could have a Choice Band Excadrill but then you have 3 Choice Pokemon and there is the chance that other Excadrill can come in after you have used another move. However, it does give you the benefit of not setting up and having X-Scissor / Return. It could even have Rapid Spin if necessary.
Paul Robertson + Scott Pilgrim = One of the Best Games Ever