[Five]

you need to look at a phases analysis when you want to work on width. width is essentially how different the two channels are. the more different, the more wide. there are mastering tools which widen stereo image by dropping the "center channel" which is everything that is calculated to be identical. so if its a pretty much dry mix with stereo reverb, dropping the center channel will only increase reverb.

there's faux stereo and other options but I would recommend leaving it alone until you get more experience. play around with a copy (personal use) and see what you can come up with.