Would be nice to have a condition on the Platform behavior to test whether it is ignoring input or not, since this is something you can set on the Platform behavior, but not (as far as I can tell) directly test for.
It would also be nice to have built in jump-buffering/ledge jump forgiveness by which I mean if you hit jump within 0.1 seconds of landing, or within 0.1 seconds of falling from a ledge, you are still able to perform the jump (automatically when you hit the ground, or immediately if you're falling.) This prevents some situations where you jump just a tiny bit late and fall, which is frustrating.
Many games also have wall-jumping mechanics, and that's something that could also be helpful to have.