That ended up looking great! For air flow, you can install a small fan in your helmet that will do a great job at keeping you cool and prevent visor fogging. There are some great tutorials here on the forums and online so there are a few ways to do it, but usually they are similar and fairly easy to do. You can get a pack of small computer fans off of amazon for really cheap.
Lighting up the sword might be difficult to do properly without cutting it open entirely. Maybe you can just cut the handle off, thread some LEDs down the sword and plastic weld the handle back on, but it would be hard to secure the LEDs inside the blade. An better way to do it would to cut the blade in half going up the inside edge, add leds, and secure it back down. Either way, I am not sure how you would be able to replace batteries and do potential repairs if the sword is glued back together