Seems to me he has no consistent rival for every arc and his closest thing to a best friend is the perv while his second in command is a magic tree.
The power of friendship is totally not a major theme.
There's 3 girls after his cock. One is the obvious lead, one is the obligatory tsundere, and the other is a plant. There's plenty more major female characters so it's not correct to say they're all after him.
I don't recall there ever being twins. If there were, they didn't show up long enough to leave a lasting impression.
Also you forgot to check upgrades because he started with just his wits, muscles, and allies, then got negation powers that he must use sparingly, then got training in how to make it more efficient, and is about to get limited copy powers.
His hair is kinda spikey. I'd say that deserves a checkmark.
And defeat totally equals friendship as far as the rivals worth making friends with go. They're not his buddies but they help him out when it counts.