When traveling to Europe or the Middle East from Minneapolis, I have a choice of going through London or through Amsterdam, using the same airline (Northwest) for either flight, with similar flight times. I go through Amsterdam simply because Schipol is clean, well-lit, organized and I have never been hassled there. Two years ago, returning from the Middle East, I had to stop in Germany and London on the way back. Went through Frankfurt on the way to Hamburg, and had no issues at all. Went on to London and then back to Minneapolis, with no real problems, but the surliness of the London employes and the dilpidation of the UK airports makes it a not-particularly-pleasant experience. I have had worse experiences in US airports in the last few years -- at Miami, in particular -- but London doesn't make it easy. This is, in fact, one place where leadership does make a huge difference: just a few pieces of paper -- written rules changes -- would make everything so much easier. The passengers would no longer argue and fight with the security people, which would make the security people happier and improve morale, it would limit confusion, etc.
Perhaps airlines should consider a "premium" ticket in both coach and business/first class, which would allow for more weight to be carried on board. It pisses me off when I see some guy who has somehow talked his way on with two huge bags (a "briefcase" that looks like an overnight bag, and an overnight bag) and then takes about three passengers' spaces in the overhead bins. But there are obviously people who need to carry small valuable items (like violins and photo gear) who need that extra space. Either that, or there should be a "secure luggage" hold in which you could check your valuable luggage for a fee, and the airline will then indemnify for any losses (including business losses) that occur as a result of baggage loss. The post office does this, FedEx and UPS do it, there's no reason the airlines couldn't do it, and even charge an insurance fee to do it.
JC