i wanna see ren vs boba fett, or maybe darth maul
Darth Maul was a very highly skilled lightsaber fighter.
He held off two highly trained Jedi Knights, killing the superior Jedi.
Ren wouldn't stand a chance against Maul.
He could almost certainly kill Boba Fett, given his strong force capabilities.
Ren stopped a blaster bolt shot at him from medium range and out of his sight.
He'd have no problem against Fett, whose arsenal included blasters and even slower projectiles, like darts, rockets and grenades (assuming Boba has all the equipment Jango did).