Dragonite - keep evolving or power up what I have?

Well this is my personal opinion but I would have never evolved this 4th Dragonite without having maxed out your number 1.

A Dragonite with DB/DC is the BEST moveset, no way you gonna get a better one, so I can't understand your reason behind keep evolving more without maxing that first to the max of your current level, and I understand it even less if he has more than 89%IV lol...

Max out the first one. Next, if you are looking for a defender, work on the one with dt. Hyper beam isnt great but he is kind of a glass cannon with that double ice weakness, so quick move is what matters, and dt hits hard.

Yup, first is the way to go. I just got SW/HB too, so I feel your pain.

My only 2 are SW/HB. I maxed out the highest IV one of those and saving my candies to try my luck on a 3rd.

You got one of (arguably the best) moveset for Dragonite already. What's the motive for evolving more instead of powering up? If you're looking for Dt?Hu, or DT/Ou then that makes sense. But if you're satisfied with DB/DC then just power it up.

In the end, the only "right" thing to do is whatever means most to you personally. I have a maxed out DT/Hu Dragonite and noww I just evolve stuff for XP.

If you are looking for an attacker, as everyone said, max A. After that there is nothing wrong imo with maxing the DT/HB one either. It does great attacking and has a dual use as a defender based on CP in a pinch.

Take number 1 to the max and put the rest on ice for now.