8 part synth suggestions for multi touch app?

I am working on an installation project where they want me to add a sound component (at the very last minute).

It is a large multi touch screen where people wave wands (with ir lights on the end) at it to make interactive "comets" (blobs).

Basically there will be 8 individual blobs being tracked at any time and they would like me to make sounds that are generated and react to each of the individual.

The most basic thing is that each blob sound is panned L/R based on it's horizontal position.

The realtime data I receive from the blobs:
unique id
x,y position
X,Y speed
m acceleration

I want to have each blob linked to it's own synth. My challenge is to create a sound that matches the visual impression of these blobs moving (some sort of wooshing/sparkly sound).

However, an important criteria is that it be low load on the cpu since the same computer will be running lot's of other apps.

So my questions are:

1. Is it more efficient to make my own synths in max (like some simple FM examples) or should I use the VST~ object and an efficient plugin that I like??

2. Does anyone have suggestions of some synthesis techniques that would match well with this application (moving particles). The realtime data from the blob tracking would have to translate into synthesis parameters that make sense.

Any tips for this project are greatly appreciated!