Hmmm, the way I see it. And I'm in arbiter-my-word-is-law mode, is that Revan wins the space battle. But Traya hounds him all the way and tears most of his fleet apart, setting them against him etc. But with each loss Traya loses more of her small force, and eventually does not have enough to pilot all the ships she has captured. Realizing her defeat on the space front she retreats to Malachor V - where she holds all the advantages. Revan breaks through her retreating line and surrounds Malachor. But of course Traya is prepared, mustering the last of her fleet she attacks Malachor and damages Revan's fleet (which has yet to engage, expecting an ambush) Superior tactics on Revan's part means the fleet is wiped out, but Revan takes losses.
With the remainder of his Forces he moves in to take Malachor, and the rest is up for debate....
So the above it basically K-Canon (Kaggath Canon
) on what happened in the space battle, based on my judgement of your arguments. So we can set that aside and focus on the final showdown.