As long as your files already contain the empty space at the tails to contain the decay of the effect and you are applying the same preset to each one, then you can use QuicKeys. I do technical pitch conversions (PAL conversions) this way. I can set it process files (sometime 40 or 50 5.1 tracks) with Pitch N Time Pro and walk away. I come back at the end of the day and re-check that it didn't do something screwy and I am done.
I am also doing some experiments with Sikuli Script. This requires some programming knowledge, but it can do some pretty amazing things. Sikuli can find things on your screen based on screen grabs. So you can tell it to find the Process button instead of having to make sure your AudioSuite windows are placed correctly. I also have a test script that yells at me for getting on Facebook, because it can visually tell the different between facebook and other web sites.
I can elaborate if need be.
Hope this helps.