What I'd love from a next-generation looper

[Len Seligman <seligman@mitre.org>]

I love my Echoplex and use it extensively as a compositional tool. I also
use it for live performance, for mostly improvised music. Of course, there
are some things that you just can't get from a looper that you get playing
with other living breathing musicians. It may be technically impossibile to
get them from a looping rig, but I'd be interested to hear from the
experts. Also, I'd be interested to hear how other musicians deal with
these limitations of currently available gear for looping:

1) I hate volume pedals as a mechanism for controlling feedback and/or
output level. This is because I feel better (and therefore play better) if
I am free to move. Standing and using a volume pedal puts me off balance.
(True, this is not strictly a looping problem, but it is much more
important when your "backup band" is a loop as opposed to good, responsive
musicians who know how to use dynamics.) Are there any alternatives to
volume pedals, either currently available or that anyone can envision? 

Here's a thought (probably crazy, but at least I could control it and still
have good balance): what about a series of footswitches that would allow
you with one press to select a given volume? Maybe 7 or 8 switches all in a
row and with a single press you select a new volume. Also, it would be
great to have the option to either make the change immediate or to have it
take place over time (e.g., a Crescendo/Decrescendo mode parameter with
possible values immediate, short, long?). Heck, can I do something like
this now with a midi pedal?

2) I'd love to be able to change the tempo of my loop without changing
pitch. This is something that is a staple of music from many cultures
(e.g., Indian classical music, much African music): get a groove going and
gradually speed it up, building the intensity. You can do it with live
musicians, but I don't know how to do it with a looped material. Any
thoughts on how to achieve this? Or is this a technical impossibility?

I look forward to hearing your ideas.

Thanks,
Len