A few answers
1 About 3500, initially, it depends on how much flying you do.
2 4-5 trips a month. Most 3 or 4 day with the occasional 2 or 5 day. About 10 nights away. When you get good at bidding (as well as senior), you can be creative with your roster.
3 Odd question. If you mean is BA a stuffy formal airline then no.
4 Mmm. Been in about 10 months and done:
Orlando, Dhaka, Harare, Chicago, Houston, Denver, Dallas, Islamabad, Cairo, Lagos, Antigua, St Lucia, Barbados, New York, Washington, Atlanta, Bermuda, Philidelphia, Newark, Abu Dhabi, Abuja, Tampa, Beijing, Bangalore, Mumbai, Bahrain, Muscat, Doha, Dubai, Montreal, Toronto. I usually get one of my top 10 requests.
5 No (Very much so). However no staff travel for 6 months.
Regards