Back to the OP
I have been told that the best effect is to use a real space.
ie. to record in the atmosphere you want the sound to capture.
Most on this forum create high-BPM compressed psytrance music so this is probably going to go to waste.
I have never recorded in a real space, the most I've done is use a convolution reverb however I have thought about recording an amp against industrial metal surfaces and I have recorded the sound in my studio several times.
As far as other effects, I have noticed that getting away from the presets is going to give you that 'wonky', as the Brittish would say, sound.
Nowdays I try to use at least one effect in a mix in the far reaches of acceptability, that is, quite abnormal sound effect.
This is due to the fact that there are thousands of producers worldwide doing the same kinds of things.