Everyone except Nihilus is a weak link.
Meetra is no less of a weak link than Maul. Either Nihilus or Revan one-shots him. Vader and Dooku's resistance to the Dark Reaper isn't a proven defense. In the game it's shown to have limitations that Nihilus can likely surpass.
Regardless of drain though, Nihilus and Revan are a stronger team than Vader and Dooku. And they're the ones who matter here.
Revan lacks any sort of saber skill, and without any concrete examples of the efficacy of his force abilities apart from ****ing gameplay GIFs I'm hesitant to say he could dominate any of Sidious's apprentices with the force. Either of them probably stomp him in a duel before he uses those flashy abilities that couldn't even kill non force sensitives on Yavin