To me reverb and other effects are like spices one adds to a recipe...some dishes need very little, some need more, some are actually based on the spice's flavor.

If I'm doing a tune using a small jazz combo style, I tend to ease off on certain effects, especially if I'm trying to simulate a small nightclub setting with carpets and drapes and a low ceiling.

For a lot of my synth and guitar solos the effects are more an integral part of the overall sound than just enhancing it.

I try to think of the environment or venue the tune is being played in and work from there.

Of course, if you are playing in a big hall with lots of echo, reverb would be hardly needed.

Again it's like adding spices or seasoning...know when enough is enough.

Ian