Really interesting points raised in the last couple of posts.
A380 and RNAV. If you get offered an RNAV too late then turn it down and you'll get an extra 2/3 minutes 'delay' for an ILS (usually extended vectoring rather than round the hold). The spacing behind an A380 is 15/20 miles. This may be reduced through RNAV approaches but if you don't feel you have enough time to set up for it then take the delay.
It can be very difficult to know the order more than 40 miles from touchdown in light traffic conditions purely because of the order they are transfered from SW or SE sectors and also how good a job they've done of getting down.
During periods of holding the landing order is fixed much further out and is much easier to stick to so there should be plenty of time to set up for an RNAV then.
AMAN. Historically spacing requirements have been coordinated by the tower as an 'immediate' request. With the advent of AMAN for Gatwick there does seem more of a need for tower to communicate the predicted time of any changes to the spacing regime for the next 60/90 minutes.
As use of AMAN at Gatwick matures I see no reason why that couldn't be incorporated into the operation.
Speed Control speed conformance by A319/320's is pretty awful at Gatwick. 160 to 4 often becomes 160 to 7. (and don't start me on traffic that slows below 180kts as soon as they're established!)
As has been pointed out this risks go arounds and missed departure gaps leading to extra delays but also if the ATCOs have no confidence that the aircraft will maintain speed then 3 mile gaps become 4 and 6s become 6.5s. We do understand the difficulty of being stable in a A319/A320 while doing 160 to 4 but some airlines do it better than others and I'm sure if GIP/GAL got together with a couple of the worst offenders then delays would reduce markedly at peak times. (On the other hand, if inbound and outbound demand is low why can't 160 to 6 be accommodated?)