If you're afraid of it reaching too far forward, you could make it like your horizontal slash, but upwards, so that it stays narrow. Or maybe an upward thrust, like Link. After all, it's Peanutbutter Gamer we're talking about, so his moveset should be inspired by games he likes, meaning his sword moves would probably benefit from resembling Link's.
I'm so hungry, I could eat Pee Bee Gee! *inhales*
I'm so hungry, I could eat Pee Bee Gee! *inhales*