This is a thing I'd really like to have - renaming of
things.
Mainly Only renaming of crafts
because other things already can be renamed. Especially in later game, I often use various weapons on aircrafts (usually five in a base - a skyranger and four interceptors; one with plasma beams for small ufos and the other with a plasma beam and a fusion balls) and it's then important to not mix them up - renaming would be a nice solution.
Also it's nice to have a soldier named after myself, etc.
I know that all this (except naming the aircraft, which is not even in the game because it just names them by their order of purchase) is editable in the save file, but I think it shouldn't be too hard or time consuming to implement one button with a name dialog.
What is quite harder is the aircraft renaming, but I know you can do it!