1) Is there a way to see how many rewards I get for the various levels of good relations from a minor faction?  Or a page somewhere that has an equation?  I haven't found this info on a wiki yet.

2) How does the political effect from the collection bonus work?  Is it like a steady drip into that party, or is it more like: every time this race has a political reaction, it is 2x as effective as it was previously?

Many thanks

#1 was staring me in the face, I found it.  But I would still like to know if it's possible to calculate/predict how much one will make before one has said relation.

3) Is it by design that warmonger factions attaack you even when you are friends?  Or will this be patched?

#3 I played a 2nd game where this didn't happen so I'm only more confused, but my current hypothesis is that if you are the Sovereign they will no longer attack you.

For #1 look at Cyrob's iter project in game help forums. Also in senate screen is an specific tab in lower right corner where you can check all bonus you get from pop types in your empire.