Practical stuff out of the way: there are some presets at the bottom to cycle through, right next to the size control!
Thanks for asking questions about who this is for. We have major label records being mastered with this every day, and testimonials from people like Mark Parfitt and Damien Lewis right on our site! People at that level use it both for the quality, and as a streamlining tool: instead of having to deal with a stack of 10 plugins, they can focus on using their ears to make adjustments with a tool that already has them in the right lanes at the right quality. Making a tool is about ergonomics in every sense. If it's hard to know what to change to get the result you want, everything takes more time. If instead, the right decisions are made ahead of time, you can focus on just the changes that you want, without having to know all details about sound manipulation, and you get a much more musical, listening-based experience instead of getting tangled in the technicals.
I'm getting wordy here, but I normally see these products in one of two lanes, neither which I love:
A one-knob or AI-based approach. No control, full trust in the machine, made exclusively for beginners or people who want "that sound"
An airplane cockpit that requires users to focus on getting technical about audio, rather than getting good at listening and adjusting to taste
Master plan is splitting the difference here: the vast majority of mastering decisions have evolved into a similar workflow across most genres. By focusing on that workflow and labeling the controls by what they do to the sound, rather than how they do it:
professionals get a more musical experience
beginners require less technical bring-up and can use their ears
everybody gets control to bend the sound to their taste
quality stays very high by picking the right decisions: beginners get help without boxing in experts too hard
By creating a one knob, we're not helping people develop their own taste or ears. By making a cockpit, we're not helping professionals get a musical or efficient experience. So this is where we land!