LA is nice ...they've added a coupe places to eat.....but IME the seating away from the open doors and birds (and bird doodoo) is always full....i wish they would have an actual place for sleeper pax other than TRAXX lounge which is only for 1st class on the CS....
WAS is nice as there is plenty to keep you occupied in the station, and the city is easily accessible.
CHI too is convenient to lots of things.
I would disagree about SEA and their staff being helpful. The station isn't in the best area, there isn't much around (though there is a tiny bar and grill outside that has really good food....it's kind of a dive, but it's clean and yummy!!) Every time I've been in that station recently I have gotten incorrect info...or NO info (re: busing on the EB when they KNEW in advance) and the agents are not always pleasant, understandable or helpful. Again, just my experience....
Also, I kind of like BOS....love the grilled cheese stand, the Club Acela is nice (but the WiFi is awful), and they seem to have their stuff together (we were bused to ALB for the LSL and we knew ahead, a conductor rode with us, and the boxed lunches we got were great!)
I guess my favorite station is whatever one I am currently in!! LOL