It's definitely a failing of the RAF not to do this better. On my sqn in Canada every chap is promoted by the CO in front of the rest of the sqn. This goes down very well and is really appreciated. We also hold 'depart with dignity' ceremonies when experienced guys leave the RCAF, these are formal occasions where the leaving member is congratulated in front of their peers and have a nice couple of hours (if they want it) during their last day in uniform.
I know that this doesn't seem very British but having seen it done a few times I wonder if we don't have something to learn.