Are there any examples of some good doom metal bands- preferably with clean vocals- that have Power Metal style/leaning lyrics? Or perhaps Power Metal bands that have some doom metal-esque tracks?
I started with Candlemass's A Sorcerer's Pledge and just needed something with a bit more of a Power-ish thing going on there. Dio was my first choice, but I'm open to anything.

While heaven Wept.

https://www.youtube.com/watch?v=YfTtzp0qn7E

https://www.youtube.com/watch?v=8DpvCaDwjfw

Have you ever listened to Dantesco? They're basically a doom/power band in my opinion. Not really clue'd in on their lyrical themes though. The vocalist is an actual opera singer and he's fucking amazing. Unfortunately their albums are too long and I never play them because of that.

I'm with you Jonpo, Their new one is 45 mins though, I haven't heard it but it probably works better.

For power/doom, you have Memory Garden (not a fan) and Abstract Algebra. But I would recommend epic doom like Procession or Atlantean Kodex since they have the tendency to be diverse and play in many playgrounds.

For future inquiries, can I ask you to use the help threads? This is not a very complicated request and it could fit in the Doom or heavy/power/speed help threads.

Whoa, 45 minutes huh? Didn't think they had any concept of brevity to be honest. I'll DEFINITELY be looking into that. I've had Pagano for years and I always really enjoy the first 8 or so tracks and then it just gets to be way too much. I think the sheer intensity of the guys vocals wear me down. Thanks for the heads up on their new one.

I've always found Solitude Aeturnus to have a power metal vibe, especially the first album "Into The Depths Of Sorrow":
https://www.youtube.com/watch?v=oFndxOc7Qhs

This description is pretty much exactly how I think of the album The Devil You Know by Heaven & Hell. Not sure if it would be what you're looking for, but how could anyone NOT want Dio on what is essentially a doom metal album?

Tad Morose fits your criteria: http://www.youtube.com/watch?v=gTJiU8wPy6I Heavy, riff-oriented PM that usually gravitates toward slower passages rather than speedy ones.

Heathendom, a pretty even split of power metal feeling and atmosphere with doom tempo, though some songs are straight pm:https://www.youtube.com/watch?v=Z1I1Tw3uxzQ

https://www.youtube.com/watch?v=eXv1Wz4ogIA

I figured such, but it was just the "Doom" and the "Heavy/(power)/Speed" that kind of turned me off as to whether I'd get accurate help. Thanks for the tip though.

Cauldron Born's debut has a couple of doomier tracks.
https://www.youtube.com/watch?v=bKNzbFY5lzk
https://www.youtube.com/watch?v=QHvaGXRO8uw

Wishdoom. they had a great record in 2011 called "Helepolis". And if you like them, then equally check out DoomSword who laid the blueprint for that kind of Epic style that bands like Wishdoom now play.