Forming a single T5CC of the class you really want takes a lot (sorry, a bit lazy right now to find a more appropriate adjective) of time. And deciding to consume one is no easy feat even when you already have a champion worth using it on.
Here's what I have:

Here's my problem:
I haven't done initial completion of Abyss and exploration of Labyrinth. I know he'll make both of these significantly quicker to finish. But after that, I'm not sure whether or not the bridged gap between rank 2 and rank 3 will be as beneficial for Act 6 exploration and the upcoming Act 7/Book 2 Act 1.
Don't have another skill champ that's more deserving of the rank up, or at least I think I don't.
This is the point where I'll have to ask for insight from the community, especially those who've already smashed the contents mentioned above. Is it worth it or not? Thanks in advance. 🍻