For clarity sake, having too many (more than 2) is a hindrance to the entire ensemble. It make everything sound very boomy & muffled.

The room where you're recording also makes a huge difference. You should professionally record rehearsals in the same room as your HB recording & listen to them to determine what you want.

If it's not clear enough due to too much tuba, cut them down to only 2 players and then switch them on the next tune/mvt.