Default [Q] simple easy question on root and 4.1.1

I'm on I605VRALL4, rooted (via CASUAL). I want to get off Android 4.1.1 because of Heartbleed but I want to stay rooted and I'd prefer to keep an unlocked bootloader. What's the highest level of stock Android that I can get to from where I'm at and still have root and an unlocked bootloader?