As of yet, nobody has put forward substantial evidence to support either side. The Sith Emperor is not a member of the Banite line, so that argument it moot. And Plagueis is severely lacking in areas in which the Emperor flourishes.
Nor do I feel Plagueis' (supposed) combat superiority is definite or relevant.
I'd certainly advise against comparing the merits of various Sith lineages which is even more irrelevant.
Agreed, unfortunately I havent read Plageuis novel so I am staying quiet on his feats. We need to really think about which one has shown more skill/ more power, but its really hard to determine when you really think about the fact that both of their greatest strengths come from non-combat abilities.
I think the big question is which is better draining a planet with the assistance of 8k sith lords to gain power, or Manipulating midichlorians.
Now personally I would say Midichlorians as, As far as i can tell, Force Drains gains are not permanant and can in fact be fleeting. The worse case of that being of course Nihilus who i believe likely would die if he didnt continue to drain on beings as his own life force was now tied into the energies he drained and because they were not naturally his own energies the power was constantly fleeting forcing him to HAVE to drain with a never ending instatiable thirst. But thats personal theory and understanding which we all know..... could be very wrong.