I find Zane easier than Fl4k at M10, and also just more fun in general. I use a cryo-centered build so I’m freezing enemies left and right and keeping my action skills almost permanently active (the mod that gives up to 25% shock damage based on action skill duration synergises beautifully with this).
The clone is as fun as ever, letting me constantly switch with it to zip around the landscape and flank enemies while it helps freeze mobs with a cryo gun or softens them up with a rocket launcher.
Overall I think Zane is the most diverse character. With my playstyle, he’s all about spatial intelligence and using the map as you juggle multiple enemies at once. Very fun, but also tense and risky.
But he can also be the exact opposite: a barrier-centred playstyle where you camp in one spot and take it easy, which is how I tend to play him for bosses.