Hi Peter and all, i am just going to mention a few things to consider as ST3 grows.

I dont use multitrack, why?
It definitely is a great tool, but only for some users that run a particular way, i myself would like to use it as a solo performer but can not see any benefit the way it is designed at the moment, it gives me no great advantages yet it could be a fantastic way of manipulating a performance on the run, the reason it is not great is because the track mutes are not easily accessible and i believe a SOLO button on each track is more valuable while performing, an easy way to just solo an instrument then solo another as an addative instrument building up to a full on mix gives the user great power to manipulate the audience , at the moment multitrack is designed to help a band replace a band member and thats it. Multitrack has more live performing capabilities if implemented to work with loops , loops are great to choose a section of a song a quick solo hit can greatly effect the mood of the song , but it could mainly helps the solo artists that use multitrack as backing, bands using click already have great capability to change the dynamics of a song but SOLO artists have not, because they need the solo/mute buttons available for instant manipulation, i can use audio mute but that comletely kills all audio and is too drastic on some songs, so a SOLO HIT ON DRUMS might give you easy beat till you decide to come out of solo on a new loop verse which then gives the user freedom to create any dynamic they choose on the run.
Having this feature would have me using multitrack as it noticably improves my performance.
At the moment stereo tracks do the same job plus i can speed up or slow down while multitracks cant do that, so for me to use multitracks the facility has to offer me some benefits while performing.
Basically i am saying multitrack is underutilized and could be a great feature in combination with loops.

PHOTO /VIDEO display capability request for new ST4 , i am suggesting a simple capability to introduce photos and video to be output to a projector/screen for the audience , either a live feed of venue or a pre programed photo or video display to be displayed on screen with lyrics on top for audience benefit.
Some uses.
Funerals, history of photos with music background , this is very common now in the industry.
Smaller shows or parties , where you could display the dance floor and pop up the lyrics , this would encourage people to get on the dance floor plus engage with singing as lyrics are displayed.

More professional bands with big production, on screen professional footage in sync with audio.

The uses can be as large or small as needed but the creating of the capability is simply load your footage and have a timeline in editor to place the order / duration and effect between the files once created it all gets saved as a song.
I know this is increasing the complexity of ST3 but thats what the audiance is expecting and why not do it all with one tool. We already have capability to display individual ST3 screens on devices for other musicians, but i dont have any other musicians to worry about but i do have an audience that would love to see the lyrics and interesting footage on side screen , to me that is more visually interesting than having old school flashing LIGHTS , perhaps a combination would really elevate the show.

These are just a couple of things i think would make ST3 complete.
Any thoughts?