I think it's a mistake to say that Elezenos "has a score to settle with us". That would imply that he resents us or our victory over him. On the contrary, I'd say the moment we defeated him was, to Zenos, the most beautiful moment of his entire, wretched life. Finally, he had found the worthy opponent he'd yearned for for so long, and faced that opponent in battle. The fact that he LOST might even have been the cherry on the cake - after all, if he'd won, then what had he to look forward to but going back to the same old grind, hoping that another, stronger opponent might eventually surface? No, Zenos slashed his own throat because, to him, his life had been fulfilled. He didn't resent us; farthest thing from it. We SAVED him, in his mind.
If Zenos resents anything, I'd say he resents the fact that he came back to life at all. He'd gotten absolutely everything he wanted out of life, and was ready to end it all - and yet, he keeps going. It was the final act, only the curtain never closed, and the actor lying "dead" on the floor has to awkwardly stand up and shuffle off the stage while everyone's watching. I've little doubt that Zenos's plans likely include a rematch with the WoL, but I think, for him, it will be a hollow conflict. Nothing can match the euphoria he's already experienced - but, honestly, what else is there to do?
I wonder if the House of the Crooked Coin is going to play into this, somehow. If anyone wants to shuffle off the cycle of reincarnation, I'd imagine Zenos does...