Depending on how hard, where, and the style you ride can definately dictate your gear. I have had my share of very serious injuries over the years and most have been with a full regiment of safety gear.
Do not skimp on the quality/price of something unless it is to get another item of gear in return and if so, as soon as possible try and upgrade items when you are able. A top quality light helmet is a must with well fitting ergonomic boots being next. Chest protector is always a good idea.
My regiment:
Shoei VFX-DT TC-5 Fonseca Helmet (one of the lightest around)
Utopia Slayer Goggles (nicest goggles)
Alpinestars Tech10 Boots (fits like a glove...uuhhhh boot)
Fox Racing Airframe Chest Protector
LBZ MX pants/long sleeve jerseys/gloves
Fox Racing Mountain Bike Padded Shorts (prevents monkeybutt
)
anddd SAND !!! The best anti rock and rash prevention around
Still can snap bones though if you digger it hard....
Sly