Hoid's secret?

Exciting stuff So from the conversation between Syl and the stormfather, we see that she wants or at least hopes Kal to be Honor's champion or play a major role in the future. But the stormfather isn't convinced. Does he already have someone else in mind?

Maybe Iam deviating from the main point here but I still can't figure out why he chose Vin? wouldnt Rashek make a better vessel for Preservation given that he had already taken up the power once and was already opposing ruin. Preservation was already dead along time ago, living on as a cognitive shadow and he clearly mentioned setting his plan in motion before he died, so I do not think Vin was intentional on his part. She wasn't even around then. He needed someone to take up his power and destroy ruin, then the HoA could take up both powers. The hero was never intended to take up the mists or his own shard before Ati was killed.

I figured that would be true, however, recall the fight between Vin and Raskek; Rashek eventually lost his metal minds and it did take a while for the aging process to take him (making him very desprate like Vin in many instances), so the spikes issue is nullified. Secondly, in secret history, Preservation is horrified that Rashek was killed, so I don't think that the help given to Vin was intentional

Could TLR have taken in the mists like Vin. Harmony's ascession confirmed that who the true HoA was, and Kel and Vin both held Preservations power for a while, but Harmony's explanantion at the end pointed that the mists could only be used by someone who had taken up the power at the WoA as the well was an 'attuning' force. Since TLR had also touched that same power, why didn't the mists aid him?