Vocals - Chase the volume not the compressor.

Ever wondered why your vocal track seems flat and uninteresting?
Sick of trying to get that perfect compression setting that makes a vocal shine?

Well, here's a different way to look at it. Don't rely on compression. That's right, it's possible to have an amazing vocal track with very little compression if any at all.
In fact, most of the time a compressor is the problem. You see, in order for a vocal track to shine it needs to be open and transparent. Full of emotional variances and tonal movement. Compressors, especially in the wrong hands, tend to flatten a performance and remove a lot of the vocals character. Ironically, right on the bits that have the most expression. Think about it, when a vocalist is raising their volume they are making a point. If your compressor is working it's hardest here, you are killing it.

With today's digital work stations there is absolutely nothing preventing you from achieving a balanced, open sounding vocal track. Start by copying and replacing the original vocal recording in your mix (must keep all originals untouched).

Solo the vocal track and play it through. Any parts that seem overtly loud or quiet should be highlighted and the amplification adjusted accordingly. (Do this in edit track mode if possible)
Start with 2dB adjustments until you get a feel for how much each part needs. Never be afraid to undo a change and try again with a different amount.
We are not looking at making the peaks all the same height or the bulk of the waveform looking the same.....
THIS IS AN EAR BASED ADJUSTMENT.

The reason you do this soloed is to get a well balanced vocal regardless of what the music is doing. Quiet and loud passages of music will fool your ears into making erroneous adjustments.

So, when you have completed this process and played the soloed vocal a few times to satisfy yourself that it's reasonably well balanced, play it with the mix.
If you still feel the need to compress the vocals, the discovery should be that you require very little to achieve a dense, transparent sound.
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Vocal Clarity

Here's a quick tip for making vocals in your mix stand out a bit more.

Play your mix and as the vocal is in full flight, mute individual channels that occupy the same space. Any muted channels that improve the vocals clarity should then have about 1dB of EQ reduction at 350Hz (medium Q). Repeat process till your happy.

This tip is about getting you to understand the fundamental issue with frequency in the 200-500Hz area. Mud often resides here, as well as an important part of vocal frequency presence.
With a little practice you can be more precise with the reductions frequency and Q.It also shows you how a problem with one particular sound is often somewhere else.

Analogy: A polar bear in snow is harder to see than one standing in a coalmine.