Hi, I hope I haven't put this in the wrong section but I wasn't at all sure where it should go.

After ten years off the road I am about to re-start serious international travel in my new role. The good part is that I'm almost a blank page now as far as FF programmes go. I have Marriott Gold and Hilton Diamond but nothing else and I'm not entirely beholden to either. To give some context about my current situation, I live in and am based in Edinburgh, UK. I'll likely be flying to and within the USA a great deal over the next two years, including some trips to Canada and Brazil/Argentina. I have no airline FF status now, at all, and only the above hotel statuses.

This means that I'm free to pick an alliance and stick with it. Historically I was always a Marriott hotels and Mileage Plus chap and reached 1K for several years before stopping travel altogether. I'd like a hotel-airline tie-in as I mainly use my points for hotel stays.

If this was you and you had to start all over today, what airline/hotel loyalty programme would you pick, and why?