Hi. I think the heart dice holds a certain amount of hit points. Haven't figured out how much it holds, yet. But eventually the heart will crack and be destroyed.
The plate kit has some sort of arrow on it like a " >" which shows the direction which dice next to it will be plated. I think it just works on normal white dice and not on orange spice or other plated dice. So when you have a white 5 dice next to its >, you should get a 5 plated dice in return.
The computer opponent will probably use the same strategy as the player when it comes to incoming damage. You roll a 14 and it sacrifices a low dice, because the higher dice could be useful later. You roll low, e.g. a 3 and it puts the damage on a dice that won't be destroyed like one with 4. Leaving him with a 1 on that dice but having still the same number of dice left, thus having still the same roll chance.
Speaking of chance, there's no way to beat this game each time. Much is based on "luck" and the crew you might get. Dream teams are repair guys giving +1 on your dice when you roll a 0. A cannoneer giving you multiple shots or splash damage. A bard to boost their abilities and a good figurehead etc.
I usually try to keep as much dice in stock as I can and then hope for the best. Good luck :)
Cargo is health, unless I am not understanding. Regular (white) dice and cargo (orange) are all counted towards hitpoints/health. The enemy gets to decide where to take damage, just like you, as the player, does. I would rather take a hit of 3 damage on a 5 die than completely lose a 1,2 or 3 dice. The enemy does the same. The more dice you have, the better your damage output is with more potential scoring dice.
Sometimes cargo is not good. If you run into a pirate ship with an unwanted potential crew member and refuse the deal, the pirate will go ahead and fight you. If you only have a 2 points of cargo, usually it will be worth it, but if you have 20 points of cargo for a 'mediocre' crew member, they will force you to fight. Depending one where that happens in the run, it can be bad.
Mates are maybe the best early game crew as you will get more encounters. So many other super great combos of crew are available, though