maplug,
couple of points here: firstly, I don't know the layout of many of the airports you quote but I do know LHR pretty well and as B&B has mentioned, three terminals are between the departure and arrival runways so the runway crossing is not so much of an issue there.
Yes LGW do a bl00dy good job as the busiest single runway airport in the world, although they presumably require 5 or 6 mile spacing to allow departures - I don't know if that results in regular holding delays for the inbounds, compared to 3 or 4 mile spacings permitted by dual runway ops. I guess you will have a better idea than me on that one.
I'd suggest it's a bit harsh to criticise the MAN ATCOs for inflexibility if you're referring to the requirements to obtain extra readbacks of holding points, given that it's now an operational requirement under their procedures. The last runway incursion I witnessed at my airport was unpleasant to say the least, probably more so for the crew of the 767 on short finals just before they went around. Don't tell me it's just ATCOs that want to ensure crews on the ground understand exactly where "hold short" means, and don't assume that an extra "hold position" is of as little use to all crews as it might be to you.