You can do multiple attacks with SS Mode.
No, you can not fire one bullet at two different targets. No matter how many minor actions to throw at it (I can't believe you are even trying to argue this to be honest). But yes, you can use
two SS weapons to multiple attack two different targets by firing each weapon once, splitting the pool and spending a minor action.
- SA can fire two rounds in quick repetition. They are both shooting at the same target and count as a single attack.
Yes, this part I agree with.
Multiple attacks cost a minor action in conjunction with a major one.
No, book actually currently don't support firing at two targets with SA mode, but a good house rule could be to treat this as two separate SS attacks while you also spend a minor action.
Another good house rule could be to allow you to only fire one single bullet at one single target (SS mode attack even though you are in SA firing mode) by spending a regular major action (but without changing firing mode).
- BF can fire 4 rounds in quick repetition. They either all go as one attack or can be split up into two attacks (splitting the pools as well)
Yes, this part I agree with.
Reason why you can't attack four different targets is because each time you tap the trigger in burst firing mode the weapon will automatically fire a burst of bullet (and also because the rules state that wide burst can only target two different targets).
with only a major action (without the need of an extra minor action).
No. Attacking multiple targets always cost an additional minor action.
Unless it explicitly say that it doesn't (see Full Auto).
- FA you are essentially completely free to do multiple attacks with one major action and without the need to spend an extra minor action.
Yes. This is the only explicit exception to the general rule that you need to spend a minor action when taking multiple attacks. You still need to split the pool though. And attack rating is reduced by 6.
Being ambidextrous, in my opinion, only bears minor tactical advantages, should the situation arise to make use of it. Highly situational.
Being able to shift between Wrest (or intercept) with a melee weapon and Anticipation with a Wide Burst firearm without spending a major action to ready another weapon is more than a minor advantage (you can't gain or spend edge on off hand attacks unless you are ambidextrous).
Depending on your build this might actually be quite valuable and well worth the 4 customization karma it cost.