"personaggio" actualy means character (in a film , for instance) , but in this case the meaning is just "person", sort of "special person", you use this when you want to specifically picture that person as something special. (is that clear??? :-/ )
Vorrei mandare un messaggio ad un amico ciclista che visita il mondo sulla sua due ruote, per dirgli che lui e i suoi video ispirano simpatia e voglia di partire. Tu sei un personaggio che ispira simpatia e i tuoi video, anche quelli brevi, mi fanno venir voglia di partire e mollare tutto e tutti per sempre.
You're a likeable person and your videos, even the short ones, make me feel like leaving everything and everyone forever.
Hi Mac, your translation is grammatically correct but a few pointers:
I’d add “very” - “You’re a very likeable person.” Otherwise it’s really faint praise - most people you come across are to some extent likeable.
The end “make me feel like leaving everything and everyone forever” sounds really extreme. Like you are a slightly crazed fan of this person, which I am sure you are not I assume it is not quite so extreme-sounding in Italian. I would just say “make me feel like dropping everything and heading for the hills” which is more along the lines of what a fellow cycling enthusiast might want to do.