I don't know why everyone I know of and those I encounter on the internet don't like Tidus from Final Fantasy Ten. People on the internet and real-life tend to say or portray him as either being overly girly in comparison with other Final Fantasy protagonists, whiny, not as well characterised and various what nots that most tend to say about most FF game protagonist anyway.
I feel that he is a nice change away from the 'angsty', 'dark' and 'brooding' main protagonist that most Final Fantasy and Japanese role playing games tend to have like Squall Leonhart, Neku Sakuraba and etcetera. He's funny, he's happy and throughout the game, he brings a smile to my face since he's so upbeat and quite refreshing, since I played a lot of Final Fantasy games.
I admit, he does have daddy issues but I think that's what makes him likeable and 'real' because he's back story can be easily related to a player who may have some of the same issues. I can't say the same for Cloud and Squall and to some extent Zidane (although he's my favourite character too) because they all have back stories that are more fantasy based (a super-powered soldier, an orphan mercenary whose somewhat an asshole to everyone and a circus thief) that I see commonly in fantasy books. Tidus is a celebrity sportsman that plays water polo underwater. For me that's new, refreshing and rather interesting for a fantasy protagonist to be and made me more curious as to how they'll develop such a 'normal' character in a fantasy game where they carry swords that are bigger then themselves and can summon magical creatures.
So for me, that was the hook and the main reason that I liked Final Fantasy Ten. His rather 'realistic' characterisation helped immersed me into the game that is very well known to be cinematic and cut-scenes heavy and almost had me teary-eyed in the end with his 'death'. (although they ruined that by reviving him in X-2 -shakes fist- CURSE YOU SQUARE ENIX!!)
TL

R? - He's more real and easier to relate to that other FF protagonists.