I had a friend (not a romantic one) that I greatly enjoyed discussing politics with. He's a Democrat, I'm a Libertarian (I called him a Socalist, he called me an Anarchist). We were pretty much diametrically opposed on everything and had great fun, I think because, although we disagreed with each other's position at least those positions were internally consistent (as opposed to hypocritical).
I have a much harder time having political discussions with Dude - even though we agree on a great number of things. Mainly because what HE considers "news" and "evidence" (in terms of where he gets his information) I consider "propaganda" and "anecdote". As a skeptic I find it a lot harder to have a rational discussion with someone with an uninformed opinion that matches mine than someone with a well-thought out opinion that is opposed to mine.
I also enjoy discussing religion - I'm a very relaxed agnostic (I don't have any answers, just a lot of questions - which is fine with me, I'd rather have no answer than hang my hat on the wrong one). I find the very concept of "faith" to be highly problematic and love to ask people to explain their take on that to me. (That same Democrat that I mentioned earlier also happened to be Jewish - we had some lovely conversations on religion as well - even though he insisted on labeling me an "atheist").
It probably depends on what role politics or religion plays in a person's life and how it shapes their day to day decisions and activities - and whether they think that someone who holds the opposite opinion is "the enemy" (or going to "burn in hell forever").
Me: poly bi female, in an "open-but-not-looking" Vee-plus with -
MrS: hetero polyflexible male, live-in husband (22+ yrs)
Dude: hetero poly male, live-in boyfriend (3+ yrs) and MrS's best friend
Lotus: poly bi married female, "it's complicated" relationships with Dude/JaneQ/MrS (1+ years)
+ "others" = FBs, FWBs, lover-friends, platonic G/BFs, boytoys, etc.
My poly blogs here:
The Journey of JaneQSmythe
The Notebook of JaneQSmythe