A LOT of stuff gets the life compressed out of it, and that for ME kills the enjoyment of some tunes - it is all squashed, generally to win the loudness wars, BUT at the expense of actual intentional building both upwards and downwards for effect.
One of my favorite albums is by Genesis, called Wind and Wuthering. On this album, there are all kinds of GIANT variances in a given song's dynamics, and they used that with MASTERFUL precision. They would create a quiet section, with delicate orchestrated piano and perhaps acoustic guitar (even a 12 string from time to time). So the listener would get drawn into this quiet background section, and then they would eventually come back with a small number of measures where they would build the sound back up to seemingly HUGE loud levels, but really it was just brought back to the same levels as were there before the quiet section. Those simple techniques CAN be extremely important and beneficial to turning a song or even a whole album into something VERY VERY special.
So, dynamics is another collection of techniques to use, when appropriate, or to NOT use, depending on the nature of the song. A song to get folks out on the dance floor may well have a kicking beat and so that sort of song may well have squashed dynamics on purpose, to keep the song hopping, so that folks are drawn to dance to it.
The NICE thing about digital recording software, such as Sonar, is that you can try multiple approaches to mixing, and discard ones that don't sound the way you want them to, without permanently impacting what was originally recorded.
I hope you find the process of fiddling with sections and parts to be both enjoyable, and a good learning experience.
For ME, I happen to both appreciate and to love properly applied dynamics. That can be SOOOO powerful - Peter Gabriel is another artist who also embraces the use of dynamics - a single note can summon every fiber of his being, and convey so much emotion - I find that to be incredibly powerful.
Bob Bone