TA contributes to Calcite Saturation Index (CSI) which is a measure of whether your water is likely to cause scaling, is likely to cause etching, or is balanced. TA can be adjusted to keep your CSI in range (e.g. to offset high CH)
High TA causes upward pressure on pH. TA can be adjusted to minimize pH drift.
To answer the question where your TA should be we need a full set of test results, but there is no reason to adjust TA just for the sake of getting it to a certain number.