Revan VS Asajj Ventress

This really isn't a contest for Revan.

Revan WTFpwns Asajj

This is not a fair contest.

Revan would win this comfortably.
I would personally say that Revan is at least as good as ROTS Anakin and since Anakin beat her then it stands to reason that Revan could as well. My reasoning for this assumption is that they were both 'saber prodigy's, both were very powerful in the Force and accomplished similar things. Anakin destroyed the Jedi temple with the clones and Revan took on the Sith temple with 2 (or less) companions (after single handedly taking out one or two of the most powerful sith in the place).
Also Assaj's Force powers are nothing compared to Revans.

Revan would annihalate Ventress with very little effort.

Revan could beat Ventress and Maul comfortably.
Revan can take on three sith masters at the same time and still walk away smiling (Darkside ending).
Maul lost to one old knight and a padawan.
Revan would do what Dooku did in AOTC and pwn them.

that is until yoda came in and pwned him back 😛
but yea revan wins 😄