Strategic bombers (SBs for short) are units that historically were really usefull back then, but somehow in CoW are pretty much useless, so i agree with you that they do need a change.
Point N°3 looks like a good idea, so does number 2, but it just makes them stronger against planes, and that's not their purpose. Altough, those improvements can be made i think.
Point number 1 doesn't make much sense because fighters are meant to attack planes, and historically fighters were bomber's biggest threat.
I posted and article a few weeks ago where i gave my opinion that SBs aren't a good unit because they are not strong on what they are supposed yo do, they do make a lot of damage to structure, but having a range of 400km at lvl 1 and 1050km at lvl 6 is not enough, most of the time you can't even attack core cities with that range, and it's even worst when tactical bombers have 750km and you can use them as "low budget SBs". If you add that to the fact that they take so long to research, it makes them useless
As a tip for using them, i usually play with the same guys as a team and i'm the "SBs guy" so what i do is to make just 5 of them and research to lvl 5 or 7 and they tell me where to attack, so there's only one person investing time on those expensive (research time) planes. If you play alone it is much harder to use them, but possible.
For attacking, i don't have too much trouble with fighters if i know where they are most active, just attack where they can't defend, or gain air superiority first. Plus, they remain on your enemy's field of view for less that 1 hour (unless you go deep in their territory, or with Allied doctrine) so unless they are an active player they won't see them coming, or it will be too late, and if we talk about attacking islands or coastal cities, unless they have fighters patrolling (not usual) they will never see them.
So remember that, attack where they can't attack you and/or gain air superiority