[Strategy]Hero upgrade options?

I've been ahead of my friend for awhile, but I've been in a lackluster phase where I didn't play as much and he got ahead of me, but now I'm starting to play more often. So now I'm trying to get my heroes up so I can go to TH10. Everything is maxed except for valks, walls (35 lava rest lego), and heroes. I just reached masters and got the 1000 gems and have been boosting drills to get DE faster while I raid. I've managed to push my queen to 19 while my king is at 16. But since I've been boosting drills while I raid, I've managed to accumulate a bunch of DE. My original plan was to work on getting one hero to new ability stage, then do the other one until 25.

But boosting for 7 days has given me head start on heroes. So if I were to upgrade queen to 20, I would already have 80K already for when I want to get her to 21. Now I'm thinking of just working my queen alone til 25, 30 and then work on king since I'll be able to start her right away when she's done upgrading and there wouldn't be any down time to accumulate the resources.

So my question, should I upgrade my queen all the way since I'll have no downtime gathering resources or still do the 5 for king, then 5 queen approach and flip flop which hero I upgrade?

Edit: kept getting hit hard so I decided to just keep on the five for one, then five for the other route.