Here are my suggestion in addition to everything Michael suggested.
1. Firearm sales from other states. With background checks done, you should be able to buy any firearm no matter what State you are in at the time.
2. CMP sales of M-1 Carbines and all other surplus firearms including M-16s (Half modified to semi-auto only, Half unmodified.)
3. Allow for full auto/three round burst firearms made after 1986 to be sold to the public. (Tax stamp?)
4. Let honorably discharged military keep their side arm and rifle as a “Thank You” for their service.
5. Reduce the tax stamp for full auto/ three round burst to $20 or less.
6. Protect all firearm manufacturers (and all related manufacturers) from any future political lawsuits.
7. Stop all bans of lead ammunition in the United States. (Use, sales, imports, ect.)
8. Protect ammunition and all its components from reclassification, manufacturing, stocking, and hazardous regulations.
9. Protect, encourage, and incentivize gun stores and ranges across the nation in urban, suburban, and rural communities. (Retroactively stop all closures of ranges due to noise ordinances.)
10. Expand ranges in wildlife areas, state forests, national forests, to include long distance ranges (200 to 2,00 yards), three gun ranges, and cowboy action shooting. Encourage this by rewarding firearm tax moneys to amount of ranges. (The more active ranges there are the higher percentage of the tax that site receives.)
11. Limit the maximum amount of insurance rates to gun stores and ranges without limiting their coverage. (Stop the price gouging that closes them.)
12. Make the price of any gun safe a tax deduction.
I'll add more as it comes to mind.