Are you using the FAS-DPD test (powder and drops) or the OTO (color block) test? You should be using the FAS-DPD.
The only way to remove copper from your pool is draining, which is one of many reasons never to use copper products.
Correct.
No, do not add baking soda. Add muriatic acid to lower the pH. The MA will also lower your TA slightly.
Yes. For chlorination, all you need (or want) is LC.
Correct. Just maintain your FC at or above the target for your CYA.
Until you get your chemistry under control, daily checks of pH and FC are good. Once things are under control, you can test FC and pH a couple times a week. You'll dose LC almost every day.
Do some experimenting to determine the minimum RPM that still achieves your purposes. Many people (including myself) run their systems constantly at low RPM.
Yes.
What's the TA of your fill water? Any baking soda additions?
MA to lower your pH will reduce your TA over time. Use full strength 31.45% MA. You can find it at Lowes or Home Depot.
Here's the best and safest method for adding MA:
Adding Muriatic