ok fair call. is it the valving in the suspension that's too soft, or is it just the springs?
Most shocks will be adjustable for preload. Depending on the shock brand, it may also have rebound and compression dampening adjusters as well.
Also, depending on the fork type, they may also have adjustable compression and rebound, hence my comment about details... If you dont tell us what TYPE of suspension you have, we cant give immediate answers as to what is going to help with your suspension woes..
Do you have adjustable suspension, or is it basic stuff? You've noted it's heavy duty stuff, but if it's bottoming everywhere and too soft with you, i'd question just how "heavy duty" it is...
If it's basic non-adjustable stuff, your options are basically to preload the rear shock if possible, and preload the fork springs, and raise the oil level or go to a heavier weight of oil.
if you have adjustable suspension, then you have the option of increasing spring preload, as well as adjusting compression dampers... Compression dampers will usually be marked as to which is which, and usually an arrow or "s" and "h" denoting Soft or Hard. Obviously, turning the adjusters towards "hard" will stiffen the suspension by mildly altering the valving, by chaning the aperture of the compression valves, and allowing less oil to travel through as the speed of spring compression rises..
and remember if you have adjustable suspension, for every action, there is an equal reaction... so rebound adjusters will also need tweaking if you alter your compression damping rates...
Tell us in more detail what type of suspension you have front and back, then we can be of a bit more assistance in giving you options in stiffening it up...