An issue with Bouger-Lambert Law
1) Yes that is correct.  Generally, when the intensity of the light transmitted or reflected is low, then the absorbance is high.

2) It is hard to say just what "most" means, but if we are speaking of visible light (remember absorbance is wavelength dependent), there are a LOT of colorless materials that do not absorb in the visible region.

3) Yes, more molecules will increase the probability of light being absorbed by the solution, but as you noted, the absorption coefficient is a "molar" absorption coefficient.  Therefor when using the molar absorption coefficient, the absorbance is adjusted for the number of molecules in the solution.