I’ve been a registered user since 2007, but haven’t used EmEditor in years due to the lack of stackable windows. Right now, you can’t have the project and outline plug-ins open at the same time without assigning each one to different parts of the screen and loosing an awful lot of space within the code editor.
I also use editplus, which has stackable windows, and this loads as quickly as EmEditor.
It really does seem an omission not to have these.