The answer is not that simple because the desired relative levels of either differ for home theater and two channel audio. For home theater purposes, a lot more absorption is desirable because precise imaging/placement cues must come from the speakers and should not be muddled by reflections. However, maximum absorption is bad for two channel audio (will sound too dry, sterile and unnatural).
Unless you are talking about really thick panels (impractical in a small room), absorption will only be effective for higher frequencies. This means you can alleviate some brightness with absorption, but there is not much you can do about problems with bass from using such panels. Bass can only be effectively treated in the corners of the room using bass traps.
Generally speaking, almost all rooms can be improved with bass trapping the corners. It is harder to predict whether any other form of treatment will be positive or negative in result. I tend to personally not like most rooms that have been extensively "treated" with absorption panels, even when the design was professionally done.
First and foremost, experiment with placement of the speakers and placement of your listening area. Most rooms are not so horrible that good placement can't cure most of the ills you are hearing. After that, I would suggest going slow -- bass trapping corners first, use of modest amounts of diffusion and some absorption (if the room sounds too bright), and, even if you think each increment improves the sound, sometimes take out treatment to see if you have overshot the mark (easy to do).
Good luck.
