From what I've been told, it sounds like the KSP stores data in discreet steps rather than continuous data. Which is odd, since in MIDI speak, CC literally means "Continuous Controller." So it makes no sense to say the KSP is sending CC data if it's actually only sending discreet per-step data.
One thing about this is that CC data is 8-bit, whereas pitch-bend and modwheel are 14-bit data. Regardless, 14-bit data doesn't take up THAT much more space than 8-bit data.
It would be nice to know exactly how much memory this thing has. Memory is quite cheap these days, even with the chip shortage going on. It has been for a long time.
But if it IS a memory issue, perhaps some compression could be used to store the data when not being actively used. Again, it's not THAT much data. We're talking kilobytes, not megabytes. Remember that all of this was developed back in the 80s when a computer with 64k of RAM was awesome. And those could store quite a bit of MIDI data, both 8-bit CC (actually continuous, not discreet) and 14-bit PB and MW.
Also, IMO, slide is not adequate, as that's a totally different thing.