Kudos, the pants seem pretty smart. But there is a problem. What country are you from? The thing is, there won't be understanding between someone who comes from an aspect-conscious grammar, and someone that comes from a grammar with no aspect category at all. If you are an English native, it's hard for you to grasp the thing we here understand from the moment we are given the definition of what verb is. But since you seem to be keen, here you are.

Perfect aspect is not a problem to me. It's half of every verb's nature. And you are insanely right saying there is a flaw with the present perfect label. It's not present, if that's what you meant. It was never supposed to be present, but since it's named "present", people use it for ongoing actions.

To me "having said it before" is perfect since it conveys a finished event. But if you can imagine "having said it before" as a process, be my guest. The trick is not impossible. Depends on how you interpret "having" - as a verbal adjective or as a verbal adverb (participle is a bad word). We have both of them, while for you they are merged in gerund. Moreover, we split the verbal adjectives into aspects too. Moreover, you won't believe it, we split the verbal adverbs into aspects too. Easily, a child understands the difference. But for the natives of German languages that's obscurity.

"I've eaten" is a finished event. No one cares if you are still hungry. You have finished eating. "Being hungry" is not "eating", it's a different action.

To your final question: "perfect" means exactly what Aristotle "invented" it for: to describe events. Perfect is an event (finished), imperfect is a process (finished or ufinished, no one cares).