I think most sound engineers and sound designers use a lot of different impulse responses to get the right depth. Plugins like Altiverb and Speakerphone are ready-made for this, but when on a tight budget you can easily find many libraries of impulse responses on the net.
Now impulse responses are very cool, but algorithmic reverbs are very handy, too. There are some excellent plugins now that rival or even exceed the quality of reverbs like Lexicon, like from Lexicon itself but i like mostly 2CAudio, Eventide, ...
Again there are always free alternatives that are very good, but often need a lot of tweaking. It's nice the more expensive reverbs have a lot of excellent presets that often are superb also for filmhttp://getthatprosound.com/the-10-best-reverb-plugins-in-the-world/
Lastly if your system would still support Powercore cards (no OSX after 10.8.4 i'm afraid) the TC VSS3 is the one i would recommend the most. It's got a complete library of presets just for film, and those are gorgeous. They're also in the TC M3000 and Reverb 4000, but why would you want to use hardware with just two channels if you can have the many instances of a plugin that is a lot cheaper and has the same algorithms.