At horizon you would could hold SEA maybe 1-2 months out of IOE but you will be on reserve for 1 year at least. Most junior SEA lineholder is a Jan '15 hire. Upgrade times maybe around 3-4 years. It's 2.5 right now for those hired back then but there's a massive amount of 2014-2015 hires on the seniority list.

You won't fly an ERJ either unless you come after Feb 2017, otherwise you will be locked on the Q.

Skywest west coast bases are all senior.

Your best bet would be compass.