> Then i guess don't give them pointy ears.
Not giving them some distinguishing physical characteristic sounds like a great way to make the work more difficult to understand. Personally I don’t mind the change.
> I remember reading they had long hair, regardless they are called something different and have completely different lives.
Some of them had long hair, but presumably others don’t. I’m not aware of any part of the Legendarium which suggests all elves had long hair. That would seem like an uncharacteristic thing for Tolkien to write about them.
> While true, in fantasy all kinds of mixes are possible that result in creatures like minotaurs, half-orcs, half-demons, half-dragons, etc., and those are obviously not human.
This is not D&D. As far as I know, there’s nothing in the Legendarium suggesting there can be unions of anything other than Men and Elves, Men and Orcs, and Elves and Maiar.
A union of an Elf and Maia happened exactly once, and is a bit of an odd becuse Maiar choose the physical form they take. Melian presumably clothed herself in the body of an Elf, at least as far as mattered.
The Men and Orcs thing is unusual in two ways. One is that it’s not explicit how they were combined. Saruman did it… somehow, but the implication is that it was through his art (magic). yhe other is that, depending on the day, Tolkien considered Orcs to be anywhere between corrupted Elves/Men, fallen Maiar, or something like animals. He wasn’t ever comfortable with the ramifications of any of these different origins had, but I think that at the time of writing Lord of the Rings, the idea was that they were corrupted Elves. I’m not super sure on that though. Either way though, I can see a lot more philosophical justification for Men and Orcs being crossed than Men and dragons, balrogs, or anything else that isn’t an Elvish/Mannish being.
Anyway, this is a long way to say that just because it happens in other fantasy settings doesn’t mean it applies here. Tolkien thought about this kind of stuff a lot, and wrote extensively on it. If you’re interested in reading more about this kinda thing, I highly recommend the History of Middle Earth series of books, especially Morgoth’s Ring, which deals a lot with the nature of existence (both physical matter and things like souls) in the Legendarium.