it depends on how you like your clothing to fit. personally, I like a taller fit with my clothes so I go for large in street wear (shirts, button downs, etc.) and XL in the sweatshirts, and I'm 5'10". the nice thing about jiberish is that it stays relatively slim compared to the length of the hoodie. the crew neck sweatshirts run a bit wider than the hoodies do. I own a large jiberish hoodie as well and it honestly feels too small for me (could be just because I'm used to a loose fit with hoodies).
if you want a looser fit (nothing under 2XL fits "baggy"), I'd go with large or XL. if you like a tighter fit, or don't like the added length and would rather have it right at your waist, go with medium or large.
I'm on mobile right now but I'll PM you my number and send you a few fit pics if you'd like.