I'll speak of butchering commercial hogs here.    The past few years, there has been a steady push from a few of the packing companies towards using Duroc boars for better meat quality.


Ours pigs are out of Landrace x Large White sows bred to Duroc boars.  They don't even start to look like finished hogs (fat) until they weigh close to 300 lbs.

If I'm taking a hog out of our finishers to the locker to be butchered for myself, I would prefer a barrow and the bigger/fatter the better, preferably 350 lbs+.      Barrows tend to be less stressy than their female counterparts and have more fat on them at any given weight.

I don't feed the one that goes in my freezer anything different than the ones that end up in the grocery store meat counter.   Corn, soy, ddgs & premix (amino acids, minerals & vitamins) ration.    Never limit feed a hog that you intend to butcher.    



As for eating dry/tough pork, not over cooking it goes a long ways.  145°F internal temp is done enough, past that you're overcooking it and drying it out needlessly.