I think a really effective thing to do concerning sound kits is to spend a bit more time producing examples of what you can do with them. I'm not sure whether the examples that you have at the moment even include all the playing techniques that are included.
Essentially what I want Notion music to do is to have each sound expansion kit have a full example video of all the techniques and after each one an example of it in context of a certain instrumentation.
-- So you might have an example video of solo strings I going like this:
(Bracketed) = what you see, "quoted" = what you hear - voice over, 'heard' = is what you hear - not a voice.
(Introductory Notion logo)
(Pictures of the recording studio, muted videos of the recording performers, clips from notion, perhaps following the music-) 'Calming, quiet, backing string quartet music' "Notion's Solo Strings I sound expansion kit offers an entirely new set of sounds for realising your compositions for solo violin, solo viola, solo cello and solo double bass, using the expertise of members of the London Symphony Orchestra. It can be used to realise solo compositions for the instruments, or as part of a wider instrumentation, such as a violin concerto." 'Meanwhile the string quartet rises into a violin concerto, impressively'.
(Picture of Carmine Lauri in recording studio on violin, title in middle in notion font (red) spelling VIOLIN) "Now for some examples..." (video shows the following examples as one would create them in Notion, playing them through) "Legato and staccato are vital techniques in any piece: here is a legato phrase followed by a staccato one on each of the each instrument in Solo Strings I:" 'Short legato phrase then staccato one played on violin, then repeated in viola, cello and double bass individually' "Now here is how you might use legato and staccato in a string quartet:" 'String quartet extract played using interplay between violin I and II and viola and cello, using staccato against legato, including the phrase heard earlier'.
This kind of thing would then be repeated for pizzicato, accent, half-step trill and whole-step trill and end with some more music this time using a variety of the techniques included in the sound expansion kit as well as other instrument sounds and their techniques.
This improvement is, I'm sure, very achievable and would work incredibly well (especially compared to the examples you have at the moment), even if it would be a lot of work to catch up with all the sound expansion kits you have at the moment.
http://www.notionmusic.com/forum/messages.cfm?threadid=7DB43B0E-C371-C73D-2CD7E0BCB7CB16EF#last
This is a link to my post in the older forum made clearly too close to the time when it became read only. It contains a notion link (strangely not allowed in this forum) to provide an example of the above (if you decide to take up my suggestion), it is merely a guide as to how you might start the Solo Strings I video (again I'm not suggesting you use it, it's just there to explain a little clearer what I've written).
I have bought the 'expanded orchestra mallets I' sound kit and there are a few small problems. Firstly, the vibraphone is incredibly useful but I have not found a way to easily control when the 'pedal' is down and up.
Essentially what should happen is that when you hit a note, depending on its dynamic it should ring a little but ultimately when the pedal is up (as it is naturally) it should not ring for very long at all (except when played rather loudly). When the pedal is down the ringing should last until the pedal is allowed to rise again or until the resonating key has stopped ringing.
What happens in the sound expansion kit at the moment is that it rings for the note's length then stops or if you have put an open tie on the end it treats that individual note as if the pedal is down and lets it ring for a few seconds before it dies away. The problem is that if you want (for example) the pedal to be held for a long time while the vibraphone plays a repeated arpeggio, you have to have an open tie on every note of the arpeggio. Another problem is that the ringing is tailored to each individual note as if there is a separate pedal for each one as you can play a scale on the vibraphone and let only certain notes ring to leave behind a chord. Realistically, this could never happen.
What should be done is that you should be able to use the pedal like in the piano. There is a feature in the percussion techniques which says pedal up/down, pedal up, pedal down, and pedal down/up. This would be perfect to have but whenever I enter I try to enter it on the vibraphone part it says operation invalid in the bottom left and doesn't do it. Although the 'unrealistic scale' problem could never be performed, I think you should keep the let ring (open tie) feature on the vibraphone to do these kinds of things and things it would be inappropriate to have a pedal down then up instructions for as it might be a single note made to ring as long as it lasts.
This problem is also featured in the chimes (tubular bells) which has a similar pedal allowing the bells to ring until you stop them, so this pedal is contrastingly naturally down, as you usually want these bells to ring until they stop themselves. This should be changed to let the bells keep ringing until they stop naturally or instructed to stop.
(I have not toiled on Notion to try and find solutions and fully test the problem so my apologies in advance if any of the above is incorrect)

Thanks.