Although this thread was addressed to loyal BA fans, I thought I would write a note from the perspective of someone who keeps up his gold cards in the two other alliances.
As I am based partly in Geneva and partly in London, BA is not the most obvious choice much of the time. Much of my travel is short haul and economy, and the gold cards are important for breakfast/lunch/dinner/drinks in the lounge when dashing from one place to the next. That saves a lot of money.
The most important considerations for mid- or long-haul travel are cost, convenience of route, and timing: followed by the choice of airline alliance as a secondary consideration. The range (and sometimes unusual-ness) of my destinations (Quito, Brazzaville, Yangon, Alma-Ata etc.) mean that the Star Alliance and Sky Team are often more suitable than BA, and the gulf airlines are not always relevant.
I am pretty relaxed about individual airlines – Egyptair, Turkish, Aeroflot, various Chinese airlines are all fine by me.
When I read again about problems checking in at T5, or at baggage reclaim there, I often feel like posting – try another airline, try another terminal.