I agree with your first two points. Point 3 I have sort of fussy disagreements with (firearms have value, buybacks tend to short change this value, and overarching tend to target already poor folks).

4. What good does registration do? Like, awesome, now you have a database with all the gun owners in it.. but for the purpose of stopping mass shooters how does that help you? Likewise, what licensing requirement do you foresee which will help with (1)?

5. Again, how does this help?