In honor of your smoking hot profile picture, I shall attempt to answer your questions.
Typical Day: I was really trying hard to come up with a smart-arsed answer to this one, but I'm too tired because today, my day started when the hotel front desk called my room at 12:30AM Central Time to ask me about our 4:30AM van time.
It's pretty much like any other Part 121 job. Day 1 is usually 1-3 legs. 2-3 legs the remaining days. 10 hour days are fairly common. 40 to 60 minute turns with some "airport appreciation" 3-4 hour sits here and there. I would guess that maybe 1 out of 10 pairings will have a deadhead somewhere. The deadhead frequency is probably higher for domiciles other than Denver.
Newhires Holding a Line: Tough one. Right now, they're holding a line within 4-6 months. Who knows if that'll continue. When I was hired, I spent all of 2 weeks on reserve. The guys in the very next class were on reserve for 18 months. 5 years after that, there were people on reserve for 3-4 years. It's all about timing and growth--beginning of the wave or the end, etc.
Length of Duty Day: Our contract says 14 hour maximum scheduled unless it's either very late or very early flying and then it's limited to 10.5 hours. Of course where Part 117 is more restrictive, the reg applies.
Legs per Day: Usually 1-3 legs per day. HOWEVER, we've recently started to see 4 and maybe even 5 legs in a day on some pairings. It's still not terribly common.
Pairing Details: From November's Denver Bid packet: 1 Day: 23%; 2 Day: 20%; 3 Day: 23%; 4 Day: 30%; 5 Day: 4%.
Contractually, everything starts and stops in your Domicile. As someone else said, if there's a deadhead at the beginning or end of the pairing, you have options allowing you to skip the deadhead.
Hope this helps.