Took this variation for a spin. He seems fun! A credible H/L game with lots of safe options, tons of corner carry, decent damage, fun juggles. I dunno how managing heat works in an actual game but those missiles are pretty sweet.
This is the variation I play when I dabble with Jax. I find Hunker Down to be incredibly boring. These virtually combo-less variations (like Kotal's Totemic) as so lame to me. Grinnin' Barret feels like a mix of two of my all-time favorite characters - Dudley and TJ Combo. I'm not sure why it doesn't get more attention.