I mean the only thing I'd complain about with regards to Cell is that he basically caused his own downfall by sheer stupidity.In hindsight Shiggy has gotta be one of the worse handlings of a character with regen powers. People complain about Cell or Majin Buu but not even those guys felt like the slog tanks that Shigaraki was. Thank God he's finally dead......hopefully
I get that it's supposed to be the Saiyan Cells that went into making him causing him to make the same mistake as Vegeta but it's still not a good look for your villain to basically hand the main cast the win.
At least Frieza couldn't have known what would happen, Cell was explicitly warned.