Digital reverb hardware programming beyond the bare basics?

Let's say we have a typical mid level Lexicon reverb and wish to program it beyond the "type", "predelay", and "length" of the 'verb.



1) What perimeter would you tweek next...diffusion perhaps?

2) What methods have you used to efficiently arrive at the 'verb you wanted...and that was not a straightforward factory preset?

Digital reverb hardware programming beyond the bare basics?