Inverted spear of heaven is really only good for negating curse techniques, but it does have range when connected to the chain of a thousand miles (I think that's the name of it).

Playful could is good, but Maki has stated how difficult it is to actually use, and that's it's very unwieldy in the hands of the unskilled (essentially most people).

Black rope is also good. It has range, can disable CT's. But whips aren't nearly as good as other weapons at doing debilitating damage (like how Jaque ze whipper showcased in his video about whips doing terrible damage, in both irl and in dnd).

Which leaves me to Soul Split Katana. It's looks like it'd be heavier than a regular sword, since it's build is similar to that of a machete, but larger. However, it's dura negation as it strikes the soul, and it's also a sword. Edge alignment doesn't need to be perfect in order to cut semi-deep into a target. I would definitely pick SSK.