I thought they were good games but underwhelming. I would've preffered DMC4, Reboot and the anime as direct followups to 3 rather than being set after 1 and non canon like the reboot.
Nero is a good idea for a character executed poorly in both 4 and 5. Outside of his connection to the Sparda twins, he has nothing to hook me with.
Outside of lady in 3, the new characters haven't interested me since. So I'm hoping the potential new characters for DMC6 catches my attention.