Since this is SkyHigh's "only happy - happy only" place you might want to repost your query in its own thread to get a better cross section of responses. But here are my strictly factual answers.

1) I was away from home 220 days last year. I commuted to sit reserve. It was difficult for me and even more so for my wife, being away from home that much. It was not too difficult to actually commute to work, however. Even though CHQ serves FAY for US to CLT, they do not have a domicile in CLT. PSA does (negative PSA comment deleted). You can commute on any carrier, not just the one you work for. It is difficult to predict who will be hireing when, but in general, it appears that regionals will be hireing unabated until the next economic downturn.

2) On reserve you are subject to call out typically in the 1 to 2 hour range. 24 hour call outs are rare, and go senior. I do not know of any airline which has a 48 hour call. Your reserve days are scheduled the month prior, and are generally not subject to change by the company. You can sometimes swap your own OFF days with your own Reserve days, if for example you are scheduled to work on your wife's birthday.

3) Almost certainly, barring economic or other catastrophy.

4) Depends. As a line holder, yes. As a reserve you can probably count on not exceeding guarantee. Which is typically 70-75 hrs a month.