It would be great if multitrack recording would save to FLAC files. These files are much smaller than wav and still lossless. Would really help being that the max recommended SD card is 32GB which can be a bit small sometimes for this task, and archiving the files elsewhere takes a lot of space too. Much better use of 32GB cards.
UI24R did this, and since switching to CQ I do miss this. Not a dealbreaker obviously as I knew this going in, but would be super cool.