My OH ordered a SPML recently for a ALC-LGW flight. While the SPML tray was present the corresponding hot main was not. It was mildly annoying for them but no biggy. CM made the appropriate notes on his iPad and left it at that.
One bag failed to make it at reclaim, baggage services desk closed due to the late arrival time (1130pm) and had to fill out a missing bag form. Called Exec Club the following lunchtime when no news had been fourth coming regarding the bag. Helpful guy on the phone traced the missing bag and arranged its delivery. Only during his sign off is there anything else I can do for you today did I think to mention the missing meal. 4000 avios offer made and accepted on behalf of my OH and added to their EC account immediately. It seemed a reasonable if not an overly generous amount (gone are those days!) and ultimately they are happy enough with this gesture. I would say 2000 would be low and had this amount been offered I would have challenged for something higher. When you saw what the alternatives were on the standard meal, you would realise you weren't missing much.