Price generally goes up with added featured, and reduced bulk at the same level of protection, or high level protection. You will notice a lot of high end stuff that is designed for the track. Many leather jackets can survive several crashes before needing replacement. The same goes for leather pants and race boots.
For gloves I'd aim for leather in at least the high impact areas. Your hands can get a lot of abuse in a crash and warrant something around or above the $100 mark to get that.
Helmets generally get lighter, and come with better features like better anti fog, built in sun visors, etc. The lower end helmets will protect you fine, but they might be noisier, not the greatest fit, or heavy compared to the better models.
Venting and rain protection are other factors to consider. Gear is useless if it's too hot for you to comfortably wear it. Or if it rains a lot where you live.