As I said, the HP weapon skills are usually notably better. Like Dartagnan's debuffs and Joan's damage cut. But the question is... is there any point in playing defensive when you can just use Herc and kill your enemies faster? Usually, the answer is no - it's simply better to Herc up and go for it. If that's not what you're doing, it's because you have a very, very specific plan and you intend to stick to it. So you have no doubt. When not in doubt... go for your grand plan.
And on a sidenote, the exceptions are the offensive weapons of Herc, Morgan and arguably Shingen are better than their HP counterparts. Shingen's Lance and Bow perform different roles, so.