An older but good approach for orchestral use is to set up TrueVerb's ER's as channel inserts for distance (ER, no reverb) then into the tail for size/ hall style ( I prefer an algo, not convo)
I used to do a front, mid, rear, perc, far rear placement this way, usually into a single tail although you can you more, or even one for each section eq'd differently to compliment the range of the instruments or sections.
TrueVerb's ER's work very well for this.