I would like an option to make the string editor display strings as they would be displayed by a Display Text trigger. The current string editor has got colors down, but in terms of spacing, line lengths, number of lines to display, etc., it's no help, which for me has meant many hours of in-game tinkering for even relatively simple text alignment tasks. Tweaking the string editor to allow for an ingame-style display would save a lot of time.
It'd also be nice to be able to click a button and have it list off all of the units that are mentioned in Set Deaths actions, so that you could know on the spot which death counters have been used. If you wanted, it could do something similar for switches, too. After all, if you're picking up a project after a long period of not working on it (I've been known to occasionally pick up work on maps that I stopped developing 5+ years ago), or working on a map originated by someone else, or simply working on a very large project where a large portion of the available units are used, it's all too easy to accidentally reuse a switch or death count, which leads to the sort of bug that can be quite annoying to track down and eliminate.
Sure, these are basically "comfort requests", but honestly, for people who are sensible and save frequently, fixing very rare crashes/bugs makes less of a difference than adding genuine convenience. Plus, some convenience features are likely to be used frequently by a good deal of the program's user base, while at this point, the program is sufficiently powerful that truly new capabilities are only going to be used on an occasional basis by a very few (advanced) users.
None.