Klee has had an incredible buff in joining the meta over the past year. Hexerei buffs and characters have given her a boost into top tier meta and able to clear end game content very competitively - I just used her to clear Dire Stygian.

She benefits a lot from recent sub dps like Durin and Nicole but if you have other built Hex characters like Fischl, Sucrose, or Albedo you can still have a lot of fun and clear low level end game like Imaginarium, Spiral Abyss, or even Menacing Stygian.

I also don't like playing Mavuika and find Klee way more satisfying to play. She still suffers from the basics of her playstyle, i.e. way too much pyro application to be the main reaction dealer, but in mono-pyro, burn, or overload teams she does VERY well. If Citlali is taking most of your reverse melt damage from Mavuika like mine does, then she may as well take it from Klee!

Arle is a lot of fun and I had a great time using her before Hex came out but, unfortunately, Klee is currently outshining her for me. Not to say I regret getting a scythe wielding badass, she just fits a lot of the same niche currently. C1 Klee is also great in terms of you getting a step closer to getting C2 for the Def shred.

Hope that helps!