I just replied to a different post (before seeing yours) and one of the things I said was the need for peak values near the meters.
Show peak values near the meters, like in every other DAW. There’s no way to know the values unless you solo and go to the Master channel (or use a VST…). The other way is sticking to the default peak references (like -24db, -6db etc). However the meters are small and hard to watch for the reference values.
In fact, this was the first problem I had with Renoise when I purchased it years ago. It’s my most desired feature. It makes a lot of difference when mixing.