Proposal: User Interface Cleanup

[SirMortimer]

I've been using Principia for a while now and maybe have some ideas to make the UI a bit more compact. This is just a proposal, not quite finished, but maybe a good start for a common brainstorming. Feedback more than welcome.

Posting here instead of discord to facilitate a better long term and archived discussion.

You'll find some details and thoughts behind them in the images.

Main window:

Plotting Frame Selection:

[eggrobin]

Came across this again while while perusing old issues; some things have improved and some are still relevant.
In particular the frame selector was redesigned entirely in #3087, which should deal with the comments about plotting frame selection (in particular tips mentioned in 4 now exist as tooltips).

• The idea of a preferences/settings/gory debugging details page is a good one.

Regarding the main window comments:

• 1.: Good idea.
• 2. and 3.: Covered by Overhaul the frame selector UI #3087, I think.
• 4.: Done in Human readable history #2373.
• 5.: Tracked by Declutter toggle #3394.