Ignore TA. Focus on pH and FC. The TA will tend to correct itself in the process of maintain the pH in range.
When working with pH & TA they will mess each other up sometimes. The only way to bring pH up without changing TA is aeration. Waterfalls, fountains or even turning the return jets up so they cause ripples at the surface will do it - slowly causing pH to rise. But, with you below 7.0 I think you need to bring it up quicker than that will allow.
Yes, pH is more important. Too low and equipment damage can occur. TA is more of a modifier that will keep pH from fluctuating too much. Now, most of my return is a huge waterfall so low pH is never a problem - high pH is. I add acid every week.So when considering the big picture, is pH more important than TA? I'm not trying to minimize any of the measurements mind you, but rather trying to learn what should have priority.
You know what??? If it would make you feel better you can raise the FC level to slam level. It will NOT hurt anything other than your wallet. That may be worth it just so you rest easy.
You have come so far...........
Kim