Thanks for the suggestions! We've debated a few of these ideas already and they might end up being implemented in the future. One that has been a particular topic of discussion is temperature monitoring. This is a great feature to have on during setup and warmup before printing, but it adds a lot of overhead during an actual print. When we print, we typically turn it on while we warm the machine up and then switch it off before starting the build. In reality, you could just enable "Stabilize temperature at startup" to avoid this all together and let the firmware handle it for you with M109/M190's. We've been hesitant to enable this by default because of all the excess overhead, but we might change our minds if we can find an efficient enough method for the future.
We also tried implementing a ON/OFF indicator for the temperature set buttons, but we quickly figured out that when we ran builds from the SD card, we had no way of knowing whether a temperature had been turned ON or not. We decided if the indicator wasn't reliable because of that, it wasn't worth including. You could parse this information from the output of an M105 command, but that gets back to the first topic of discussion since that now requires you to constantly issue these commands potentially slowing down the build and impacting print quality.
And can you provide a bit more information on this last point? How do you typically set the first layer temperature? You can easily add multiple per-layer temperature setpoints so you can have a temperature defined for layer 1, 2, 3, etc.