Little confused and stuck on which account to focus

Basically my Nyx account I’ve had for about 26 days longer than the Khamet account, but both are relatively stuck in the same spots. I can do GR1-15 with Khamet’s account no problem; but just this past Saturday, I finally beat GR1-13 with Nyx’s account.

On the flip side, I can only do GR3-13 with Khamet’s account; and Nyx’s can do all the way to GR3-16.

When it comes to the Guild Boss, my Khamet account can do 15% to Nightmare 2; but my Nyx team can’t even make it past the second fireball attack (460blood), so it’s been stuck on Nightmare 1 and Hard.

I’m just kind of confused really, I feel like I’m stretching my brain too thin, focusing on all these different things, and I need advice on which one to focus as a primary.

(Also, I’ve been saying forever, that if I could get them merged, that would be so amazing, because both sides lack what the other has; but I know that’s not realistic lmao)

TL-DR: which account should I focus on?