This is more in the nature of feedback on the product than a specific feature request, though a suggestion or two may be found here. I'm working with the Windows product.
Neither in the product itself nor in the online handbook have I found a place to offer feedback that is not intended to be either a bug report or a feature request, but more in the nature of a suggestion or a comment. That omission may be deliberate, but if it is an oversight you might consider providing for two kinds of feedback: on the product itself and on the online handbook.
When saving files it would be nicer (in Windows at least) to have the default file names have spaces rather than underscores between the words in the name. You may have good reasons for the underscores; I don't know what those might be. But if it's just a carryover from Linux, for example, and you could make that difference in the Windows product, it would be nice.
I play the musical saw, and I sometimes write for it. In checking the voices available under All Instruments I find a musical saw listed under Pitched Percussion, but it is the sound as played with a mallet. That is indeed one way the saw is played, but it is more commonly played with a bow and that's the sound I'd prefer to use. Only no such sound is in the lists. So I went through the lists checking several other sounds, including these: Musical Glasses; Kazoo; Virginal; Harmonium; Bowed Synthesizer; Saw Synthesizer; Theremin; Erhu. None is right, though Erhu comes closest. I was surprised particularly that the Theremin sounded almost like a percussive instrument, with a strong attack. I've never heard one that sounds that way. They sound much more like a Hawaiian guitar (without a plucking sound), and a well-bowed saw sounds similar. (By the way, I didn't find a Hawaiian Guitar in the list either.) If you ever expand the lists it would be nice to find the Hawaiian Guitar and Bowed Musical Saw added, and perhaps the Theremin sound replaced with a more realistic one. (That might require renaming the existing Musical Saw item.) There might even be merit in adding a category named Esoterica or some such for instruments that don't fit well into the existing categories.
Regarding the musical saw pitch range (for showing out-of-range notes in red), there are quite a number of custom saws out there with a variety of ranges, and therein may lie a problem for determining what range to assign (unless you create multiple voices for saws with different ranges, which I doubt you'd want to undertake). The most common range for off-the-shelf hardware store saws (of which very few now exist that can do good music, Sandvik/Bahco being one of the few remaining), is from C4 to F5. Saws claiming to be tenor or baritone saws will go lower but not as high. Longer saws will have a wider range. The effective range is determined partly by the length of the blade and partly by the width of the blade at its wide and narrow ends. Wider at the wide end goes lower; narrower at the narrow end goes higher. I did note that the musical saw item in the Pitched Percussion list showed E4 and below and F7 and above out of range. I would contend that those are inaccurate. Yes, a saw can be forced into harmonics that go up toward that upper note, but very few players know how to control that for real music; it just isn't practical. (Some saws do that more naturally and easily than others.)