The main problem my finished tracks have is a poor quality vocal sound. I generally try to apply a dynamic range compression filter first and then add some reverb/chorus as appropriate but I can never get results that are good enough. What do you suggest is the best way to treat a good, untouched vocal take?
Definitely EQ. if you're not using a super-high quality mic then there's going to be a need for frequency compensation, and a good bit of EQing can make even simply lightly-reverbed vocal tracks sit much nicer in your mix.
Also, don't drown your vocals in FX (unless that's the aim of the track, or you're using a vocoder ;) ). A good plate reverb, maybe a smidgen of delay (with automation to accentuate key words/sounds) and a little EQ will generally do the business.
What happened to dynamics?
Depending on the situation, I use the following:
EQ -> A little compression -> [monitor out for singer] -> Multiband compression aka de-esser -> compression -> reverb
Everything pre-fader except for the reverb.
The first compressor is just making things a bit more comfortable for the singer and really shouldn't do much. The de-esser is not always necessary, but some singers need it, especially when recorded with a large diaphragm condenser. It should not be set up to make a huge difference either. The last compressor actually does the 'real' job. :)
Compression, for me. Properly adjusted, will make your vocal more punchy giving a bit more impact to the song, as vocals are the most noticed things to listeners.
A very good sounding, easy and cheap compressor is in TB Ferox. Notice this will also bring up whatever is between the words, such as background noise.
If the voice is a bit muffled, you can try adding EQ above 15 kHz or such. It will sound more aggresive.
Generally, however, other FX won't help with a not so good voice recording. If you feel the voice can't be made to sound decent, you definitely need a better recorded sound, probably in the order: better mic > better preamp > better room (taking the actual singer's voice out of the equation).