Mercury-main

The biggest problem I noticed almost immediately: Where your cross-guard connects to your forte isn't flush and there is a gap in that (what appears to be rubber) coating. Dirt and moisture will seep down in there and rust the blade out, and weaken it. (Easiest seen in Grip 2)
That, and the material at that section appears to be rubber. If you're doing anything theatrical, you're going to get that piece all nicked up and rather destroyed if it's anything but metal.

Second problem, and I'd actually have to hold the thing to be sure, but the grip looks rather awkward. I see what you were going for, but the dips verses the little knobs on the peaks of the segments look rather awkward for a grip. Since you're not baseball-bat holding a sword (your fingers should be slightly slanted up towards the blade), that just seems like that would feel rather awkward to hold.

Also, more or less curiosity: The purpose of it looking segmented at the hilt?
It seems like those segments would be removable, but I see no real purpose in that without removing them all at once to access the back-end of the blade.

For vision aspect, it would be nice to see some function out of the pommel. Since with a katana no part of your hand will ever really grip the pommel as you would with a European sword, you could do something special with that, like put a small secondary blade, spike, something ornate, et cetera. (usually easiest accomplished by just having the part of the blade that extends through the grip just being a bit longer than usual, to keep the entire sword structurally sound vice adding something else on). It's hard for me to tell but here it just looks like another piece.