I don't know if this would solve it. Rather, it might be useful to have an envelope icon that turns a different color (or some other visual indicator) which highlights new responses to a post.

The daily-sat flag could remain on the wallet balance (as designed today).

This approach would separate community replies vs sat stacking

could you like bold the stacked wallet balance, or like 3510 \ 4125 [121] <-that indicating your daily stack from participation.