pipeline, I knew it was too good to be true smile The idea for the custom GUI selectable with CTR-T is OK, but Cakewalk has it better, because you can have several custom templates switchable in single project. I guess what you proposed will work almost like that. If it will be implemented one day, it would be nice, to be able to save that "custom" template as a file and have a couple of different ones, also, if it is in a form of file you can easily share your favorite GUI template with fellow users.

Flexible GUI... is among top 4 of my requests. If you count overhaul of MiXeR (which could be interpreted as part of GUI) among top 3 requests.

If I had my way, I would publish BIAB with NEWer GUI (2017?) on the start, so new users do not freak out by insane amount of buttons jumping at them and do not discredit the program, judging it by initial appearance. Seasoned users know their way around! If the want to go back to "old look GUI" all they have to do is press SINGLE BUTTON and life will be happy again.