Hi, I'm new here, and relatively new to air travel, but I think at least 1 of my questions is correct for this thread. I'm traveling from Syracuse, NY to Walla Walla, WA for a job interview. Here is the outbound itinerary my potential employer has chosen:

Delta 6066 Depart SYR 0605, arrive DTW 0750
Delta 2149 Depart DTW 0840, arrive SEA 1041
Alaska 2096 Depart SEA 1255, arrive ALW 1351

Question 1, is 50 minutes enough time for a connection at Detroit at this time of day? I checked, and I have to get from terminal C to A. From this thread, it seems sufficient.

Question 2, I've never changed airlines in the middle of an itinerary before. At Seattle I'm changing airlines from Delta to Alaska Airlines. Will the suitcase I check in SYR make it all the way to ALW? Or will I have to pick it up at the baggage claim in SEA, and then go to the check in desk and recheck it with Alaska Airlines? And if I have to claim and recheck my suitcase and go through security again, will my 2 hour 14 minute layover in SEA be sufficient?

Question 3, how would I go about checking in online and printing boarding passes for my flights the night before? Would I be able to check in at both the Delta and Alaska websites? Or would I need to only check in on Delta's website and see how the luggage situation plays out before checking in with Alaska at the check in desk or gate?