When mixing down and adding reverb, in general, should I use the same type of reverb on all my tracks with different send levels, or does that really not matter. I'm mainly thinking in terms of guitar, keyboards and vocals.
Too much reverb will muddy up a mix!
It will do so even with one patch setting for all instruments. Use effects sparingly.
However using several different reverbs
(Small room for kick drum) (large hall for snare) (Delay on guitars) etc.. will not ruin a mix. It will instead create a spacial depth
for each instrument, and can really liven up a song. Just don't over use any effect.
Panning can help to separate intruments also, and you can send a dry signal left and a "Wet" signal right, for a neat stereo effect!