Well - it depends on how you want it to look - blues and greens will convey a feeling of "eeriness", a really yellow, dim angled from directly above gives a very shadowed, high ceiling, dim light feel (so use CTO)...
In what context are you doing the show - naturalistic or abstract. Best bet, try a number of gels using a swatchbook (free from most gel suppliers and manufacturers) - colour is a very personal thing.