FX are far better applied to a dry mix..... to eliminate any ambient or unwanted echos is the preferred option. It is better to keep the wetness down and gradually re apply fx on low almost dry settings till you get the sound you want. It is important to note that each style of song and every voice is unique and people have diff tastes in fx so there are no rules for what is good or bad.....only what works for each application and your own unique voice. Experimentation is the only answer....Personally I use very lttle reverb and use a very dry mix. My tip is to duplicate the vocs and apply fx to that track only then the main vocs are kept clean...fx can then be added to the duplicate and volumes adjusted till the sound you prefer is reached. When both tracks are played back the FX are lessened and sound more natural.
I would suggest investing in a decent studio mic as better results depend on the quality of the clean recording and not so much on how much FX are applied.

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