I have always believed that Hoid was trying to help the 'good guys'. I believe that Hoid is a good person, who has the ability to hop from planet to planet, maybe due to being connected somehow to the shards.
Note, Hoid became a leader in WoA, leading the leaderless Terrisman to a safe haven.
In draft version of WoA, (and I'm pretty sure final draft as well), he broke the pottery, either to help Elend/Vin, or because he was curious.
In Elantris, he was helping Sarene help the Elantrians by smuggling supplies in.
And in Warbreaker, he gave Siri the information she needed.
In FE, he gives Kelsier pretty decent information.
IN HoA, it is assumed that he would've given Vin some pretty good info too.
So, I think that it is more than coincidence that Hoid always finds his way to the heroes, and helps them out. I think that he's a good person, (or maybe even a guilty person), who wants to help the heroes. Whether or not he is trying to reform Andonalsium, I'm not sure.
If he is, he's one step closer with Sazed holding two Shards.
Oh! Idea! Maybe he manipulates the Shadesmar(see edit) so that he can reach the Spiritual Realm, where all of the Shards are still vaguely connected. He than travels that way to planet hop from Shard to Shard.
Maybe a way to see how Andonalsium shattered is seeing how Preservation passed away. Maybe Andonalsium's mind 'broke' and so he died, and Hoid gathered sixteen (or whatever number) people to take up the power. Or maybe Andonalsium shattered on purpose. Who knows?
EDIT- I used Shadesmar wrong. I know that there's a word out there that Brandon used to say how Hoid got into the Well of Ascension Area..... Was it in the Annotations? No, I think it was in a recent Q/A..... I'll try and find it.