Maybe the so called health bars can just be color codes, like green for 100% and yellow, orange, red, or whatever for lower levels and maybe its possible that the accuracy of these types of references will depend on the quality of crew you hire. Since I haven't played this game yet and it is not completed yet either I don't know if the officers are hired by price depending on their level of experience but I think that would be a good idea either way.
Otherwise I'm also against having a health bar type thing that shows precicely 78% or 34% for each side or stern, etc. like it was in POTBS. That game was fun in its own way but you knew right away after about 1-2 shots from both sides who was going to win and could then decide whether to run off.