Hello, I've lurked for some time and will be starting to fly quite a bit for work and pleasure. I would be interested in hearing your thoughts on the best program for me.

Background:
- Will be flying around 75-100k miles a year
- BOS is my home airport
- most segments will be east coast/canada (business)
- most miles will come from MRs/Leisure trip/s to Asia and Europe (play)
- point wise, I have a couple hundred K miles at both AA and UAL, but no current status (expired a couple years ago when not traveling)
- new to BOS, so not sure what the best MR here are
- favorite cities to fly to (Asia): SIN, BKK; (North Amer): LAS, LAX, SFO; (Europe): UK, Italy, France;


What I'm looking for:
- primarily use points/status for a decent shot at upgrades, including intl. flights
- leg room when in economy
- stability/health of program
- Availability of mileage runs/deals
- quality of lounges and service
- little to no BS charges to book alliance flights, upgrades, etc
- less important, but important is the ease of booking alliance rewards

obviously AA and UAL are the front runners due to size, but I'm open to a foreign programs in either OW or SA alliance.

What I would like to hear is what you would recommend and why (based on the above).

Thanks and I look forward to your response!