Enemy difficulty isn't any different other than adjustments to the ones they just released with mistlands. Nothing you would have been around to notice changes for since those monsters were both introduced and then altered while you were gone.

Then regarding stamina, the food is now broken down into more specific stamina/health/mana foods with a few that split health/stamina evenly. If your short on stamina its because your not paying attention to what foods do. Alot of people had that problem after the hearth and home patch but its just a matter of learning how to balance your foods differently. If your having problems with stamina while farming eat three stamina heavy foods.