Wow, I don't know where to begin.
Cleaning up production sound is one of the toughest gigs in audio post. It takes quite a long time to develop the "ear," and the better processing systems are fairly pricey.
Part of getting good dialog tracks is editing and mixing line by line, word by word, syllable by syllable. But as the programmers used to say, GIGO - Garbage In, Garbage Out. It all starts with capturing quality production sound. If your production sound is poor your audio post becomes a rescue operation. At the low/no/mini/micro budget indie level the best you can hope for in audio post is intelligibility.
Start with reducing broadband noises and excessive hiss. Notch, high pass and low pass filters can handle this. Then lower the volume between lines of dialog. (Actually, you should cut these spaces out and drop them onto a separate track with appropriate crossfades.) Then you start tweaking. The basic issue is to keep the sound of the dialog consistent within the film as a whole as well as within the scene.
Audition has a noise reduction processor. If/when you use it do it in small judicious bits; this is one of the "secrets" in cleaning up production sound. The "big guys" will have four or more (very pricey) noise reduction plugins on each channel rather than taking the brute force approach.
Oh, a learning tip... Once you've completed your dialog edit be sure to save an "original" copy so you can A/B your progress as you work on the noise reduction.
... You DO NOT compress dialog tracks in the way that you probably mean it.
... If you get the "weird reverb effect" you are probably over processing or over compressing. Removing existing reverb is difficult even for the pros. There are a few processors that help a bit, even a few free ones, but nothing beats capturing solid production sound to avoid the problem in the first place.