At one point, we had the name of the model on each channel in the Test tab, but that broke a lot of the export routines. I'd definitely like to revisit that a bit, but have other v4 things that are a higher priority.
When I setup my outputs this year, I used much larger outputs than I planned to use. For example, my DMX universe 1 I only planned on about 30 channels, but I has it set to 96 channels in the Setup. DMX universe 2 was similar, had 64 planned channels, but setup for 96. DMX 3 was my "komby wireless" universe where I originally planned on 4 Raptors (48 channels) but was setup for 192 channels. When I then moved some stuff from DMX universe 2 to MiniRens on the wireless, there was plenty of room and didn't need to re-order things. Yes, there are a bunch of blank channels being output, but that's OK. Doesn't really affect anything.
One hint: keeping outputs in multiples of 3 allows for the RGB testing to be a bit easier as the RGB channels would line up correctly if you "select all". Thus, 96, 192, etc work well, but 128 doesn't.