I picked up a good tip from watching a Morgan Page interview the other week. Helps with mixing the low end. If you stick a bit crusher or some distortion (something that generates higher harmonics) onto your sub basses then you will be able to hear the volume envelope of your sub a lot clearer. Helps with setting up sidechain compression etc.br
Also, building on that if you stick a bit crusher on both your kick and bass and set the downsampling to different levels so you get a different tone from each, you can hear how much they overlap one another. I find it works really well so I thought I would share. Unfortunately this won’t help with highlighting frequency clashes in the sub region though. You will still have to use a spectrum analyser and your ears for that.