If you want him dead, no. Well, he's nice to have around and has his own subplot. He's not necessary to complete the game though.
You don't need the bastard. You can complete the game without him but you lose a part of the story, and if ya need a healer well you could get yoursel Raven or Perriman
Stange coz I've got 8 CHA and I can't join Dante because there ain't enough room and I have Virgil and Magnus in my team
Just tell either Virgil or Magnus to wait, let Dante join and then let Virgil/Magnus rejoin. That should do the trick. You won't regret having Dante in your party. Apart from being an excellent healing priest, he's a true warpig, going all the way up to 20 ST. Blasphemeurs and orcs better watch out...
IIRC, You'd have to make Virgil or Magnus wait, let Dante join, tell Dante to wait, let Virgil/Magnus rejoin, then let Dante rejoin.