I'm just sharing something I discovered this week about how to easily see both pre and post fader meters to make gain matching easy. It's probably nothing new, but I haven't seen it anywhere. I think Reaper should have this as a native function, it's really helpful to see level differences and help to match them so that A/B comparisons make more sense.
using the JS router (combiner?) plugin as the 1st plugin to send 1/2 to 3/4, then have to open up the channels in subsequent plugins to pass the audio through (I think??). Pre fader is then displayed on channels 3/4, and post fader/post processing on channels 1/2. Using this on every single track and buss now (except FX returns and parallels), and I'm wondering why this isn't just standard practice??