In multi-player playing with friends I was always fairly good with scrums and it was almost a quick-draw thing in the past. I could win ball quite often (maybe 1 against the feed every 6 scrums), so it was quite good in that way.
In single player I'd totally agree with you Nick, it just wasn't quite right. I'd like to feel that you could use some tactic to out-muscle and push your opposition off the ball. Sure in real life it doesn't happen too often, but in a video game, you need a small contest within the greater game, something to make the scrum..... something. At the moment it's a little one dimensional. As I said earlier, feeling that you'd worked hard to push the other team off the ball would be rewarding.
The idea above would obviously be an "advanced" option, but it would take no longer to get used to than the controls for an fps to be honest.
I'd like the idea of using the pressure of the drive forward (left stick), in conjunction with the slight upwards and downwards pressure that make the difference within the forward pushing in a real scrum.
Perhaps to continue this line of thought, there could be a halfback feed option. Before the scrum mechanics occur, if you have a weaker scrum, your halfback can throw the ball into your side of the scrum, but there is a chance of being penalized.