I agree, it's actually quite elegant once you get used to it
Indeed, there are some issues like the TAI mini map popping up when it should stay minimised, and the stopwatch/clock disappearing when you drop back from 64+ TC, plus there are a number of missing features that really need to go back in, to save you running to your crew.
But otherwise it's quite functional. I haven't yet decided which type of UI I prefer overall, but I certainly don't dislike the default UI.
I haven't added any hotkey mods yet or made any adjustments myself, but I'm starting to miss a few things so won't be long now.