The ability to use user-defined bookmarks in long documents would certainly improve document management.
The selection tool currently implemented is not very handy. A lasso tool would be better.
This feature was implemented in WRITE but that application is no longer supported so that's the reason i'm using squid now. In addition to a simple vertical insert/remove, a horizontal one with an automatic displacement of conflicting text would be much appreciated. Otherwise, it is way too similar to real paper: it is so awkward to make corrections...