Finally get to start giving some feedback...
FDev, I think your ideas in the OP are a reasonable start, but I suggest they need modification and considerable expansion to bring meaningful gameplay. The main issue I see is lack of strategy options. I hope some of the ideas in this and other threads are adopted and what we see in the OP is not a fait accompli.
My initial (admittedly very crude) feedback is that while the discovery "tune and focus scanner" seems to be a nice new mechanic, I agree with some posters who say it could easily become a tedious time-wall. Sure it might be cool for the first dozen systems, but 100? 1000? Uh, probably not.
Also, people are calling the new mechanic a mini-game, but really it's just a process or procedure. Once that process or procedure is learnt, it's hardly gameplay. Having said that, every system will give different frequency spectra / patterns, so there is some gameplay. But that mini-game / procedure also becomes a core gameplay mechanic. Every player will be doing it as part of their day to day travels, even if only to interpret the initial honk signals. And explorers will become permanent human signal analysers, very strange given that computers are so much more suited to this task (more about that later).
Ofc I've been around long enough to know that this new mechanic will be part of the game, in some form, so it's our job to try to make suggestions to make it rewarding, fun, even exciting? To that end I'll post later with my thoughts on giving players far more options alongside the manual frequency analyser approach given in the OP. These will revolve around a discovery computer (for signal analysis) being an inherent part of the ADS. Players should be given the option of using the OP manual approach or a configurable (but ironically slower, for game balance only) signal analysis computer. Such a signal analyser could introduce a very nice strategy element, where the player assigns CPU % (or QPU % - quantum processing?) to the various frequency bands and or range bands of interest, thus hastening analysis to the explorer's specific interests - a bit like an equaliser is used in hifi playback - but in more dimensions. This probably makes no sense yet, but my intention is to write this up in coherent form later.
In short, the aim should be to give players options. The manual (OP) approach which will actually give more info in a shorter time for those who wish to make the effort, or a slower configurable discover analyser approach. The ADS hardware / software needs to cater for every explorer type, as it would IRL - the hard core explorer, the casuals, the cherry pickers, and ofc the non-explorers who just need a no nonsense system map. More later!