Reverb / delay

Delays shorter then 40 ms sound as if they are part of the original sound, i.e. they do not sound as an echo

Adding very little short delay (1/128th) to something can make it bigger (try panning the delay differently)

Use a predelay (1/128th) on reverbs to get a clearer sound

Set decay for the 'master'-reverb to 1/2nd

Assuming you like a 3/16th delay on a track: increase the delay time a bit to make this track seem to go slower, decrease the delay time to make this track to rush ahead

Remove low end from reverbs to make the mix clearer

Remove some top end from one side of the (stereo-)reverb to make the sound coming from the other side

Add reverb only to the attack of a sound (f.e. drums) by sending the sound onto another track and compress it very hard (so only the peaks get through), now add reverb to this track alone