All the above are valid as far as they go; but you must be prepared to defend your point of view:
Rats: Yes, shooting is a good option but as far as real control in a domestic situation goes I suggest it is not a complete answer. Poison bait traps can be set and left and judging by the number I see around buildings (e.g. B&Q, a local hospice) they are the means of control favoured by pest controllers. I suggest shooting is not the diy option available to the vast majority of people.
Cats: Is there any evidence to support that it is mostly retired people who shoot cats rather than youngsters? My opinion, for what it is worth, is that it is most likely the tennage thug, but I have no evidence. Just stress it is already illegal to shoot cats and do not dilute your argument by stating facts you cannot support. Or can you ....
General licence ... agree, that is the best stance, maybe stressing public health issues, contaminated grain etc, magpies and attacks on new borne lambs etc.
Cheers, Phil