It is not uncommon for me to have different ranges for different instruments pitch bend wise. Also you are limited to only a small range octave wise.
I use simult pad for certain parts of the sound that you do not want to be affected by the pitch shift you get from making chromatic scale....
For instance say string scrape, or hammer on noise. So this means every pad say on the first bank will play in chromatic pitch but also just one simult pad as well, say 16 or on another bank. This unpitched element of your sound can be then key split to. So for instance I make bottom octave C1 to C2 have a lower pitched hammer noise or string noise, but it is only for that octave as I set it up to simult all those first 12 pads in the octave to simult the same pad, that is not pitched, with the hammer noise, string scrape whatever. Then repeat this but with another different simult pad sound/sample for a second octave up or down for realism. This is a manual way to do it of course.
See the problem is this does not work in mono program, in poly mode makes it harder as you have to actually sequence it that way, legato wise. But if you want unpitched sounds as part of pitched instrument then thats a good and easy way to do it I think, the simult pad trick. But it also means you can have sample play but with added attack sounds, then no attack sounds when you change to another pitch. makes sense?? so it is like sample does not restart but it does, when going to another pitch. but only here the attack sound when you want, say by using velocity switching layers ect.
So this makes me think that it would be a new request for the two settings to work in tandem and not one or the other when it comes to mute and simult pads. Because instead of instrument I do above method, its a shame it does not work in mono mode for that legato feel right. Why not though, i mean if you set it up right then it would be way cool, to simult pads but they also mute target/group. So I set all to same mute group except the unpitched simult pad and it will play like mono but also simult pad at same time, which is poly mode, giving you legatoish feel. That would be an interesting request i think. and would facilitate mutisample instrument creation a lot better. not for portamento though, that would need instrument program.
this would be really good to, as with the velocity layer switching to, say for harder sounds add another layer. that is what i do, so it sounds like a harder sound with added layer over a certain velocity being triggered.. its been something like a year since i thought shame these do not work in tandem the simult and mutes in program.
I never used the simult play and velocity switching the other way though till just now so thanks for that. So instead of velocity switching the layers of first pad hat I hit, I do it just to the pad that is the simult play one. thats great. but for that legato you need mute and simult. I do not mean changing pitch by velocity layer though as you can do that to.
Do you think that would be closer to it? it means you can even chop and loop the sounds for instrument, simult pad has attack, then other pads have the rest of the instrument sound, even looped so it goes for ever if held. that is what i do i use loop then hit both at same time to stop and start a differnt pitch. that is my work round for simult and mute groups not working together in harmony.
We aren't going to get better time stretching because 1) these are proprietary algorithms and it'd have to licensed ($$$$) and 2) the CPU is not up to the task. 
