perhaps you should read a little about the plug-ins you've spent so much money on
different compressors use different level detectors. basically just because both compressors are Waves, doesn't mean jack. that's like saying any Fender guitar will sound the same, because they're all Fenders.
How can you expect to use these tools without knowing how they work? i don't mean that you don't know how to use a comp, i'm just saying all these comps have different characteristics and you can't use them properly if you don't know how they work.
and i don't think it's the 125hz roll-off that has affected the EQ of your voice. how far do you stand from the microphone? it's either that or you're using the wrong mic for your voice. try re-recording standing closer to the microphone.
do you understand how a compressor works? what all the buttons do? do you know what compression is? it's easy to have some sort of abstract thought of what a compressor does but unless you understand precisely what each parameter does and how it will affect your sound, you're gonna have a hard time getting anything to sound good.
read the waves documentation..read about how different compressors (VCAs, Opto etc) work and then try again. you'll find things much easier when you understand the tools you've got to work with.
oh, and i'd redo those vocal parts if i were you, and try to get a "fuller" sound. try and move closer to the mic if you're standing further away. if you're not, try moving the mic, or try a different mic.