Have a read of Dans two posts that I have referenced. Very interesting reads.
Vests/Steem Power are like an option to convert for certain fixed amount of Steem.
Reputation isn't directly related to steem power. You can't "buy" reputation but rather its something that you get from participating in the platform.
Does it reduce the impact of your upvotes?
Just read them. They're fine articles, but I guess what I'm still uncertain of is: is Steem Power the only factor that goes into the impact of an upvote? Also, I guess, what are the algorithms that dictate trending and hot?
Not that I know how to make content that uses those factors. I write fiction, mainly, but I'm curious. I like understanding games, and I feel like I don't exactly know the rules. I though reputation was what made a whale, but it's not, is it?
The amount of Steem power you hold and Voting Power are the variables that determine how much your vote is worth since HF19. i.e. Voting power means the more you vote in a day the less your votes are worth until your voting power recharges.
Your vote will also be impacted by how many votes have been cast in the day by other voters on other posts and how much the price of Steem is.
According to Steemit FAQ
So hot posts are posts that are getting the most upvotes or comments, trending posts seem to be the same but stake weighted.
Got it. And reputation is how much other reputable users have upvoted you ever.