You're not the first to question Hoid's motives.
Look at this topic:
according to Hoid himself, he is not a good person and should not be trusted
As for Hoid's powers: a form of immortality derived from a remnant of the weapon against Adonalsium; ability to manipulate Connection to a place to know the language spoken there; ability to access Fortune to know when and where he is needed; time dilation: he hadn't experienced all the time between the Shattering to now; ability to heal both his Physical body and his Spiritweb, possibly the same thing as his immortality; Yolish Lightweaving which he uses in his storytelling; Allomancy from ingesting a bead of Lerasium; at least 200 Breaths, which he can use to Awaken, he's at least of the Second Heightening; Rosharan Lightweaving and Soulcasting from Bonding a Cryptic