Yep, I fully agree with Guinness; I moved my DM10 Studio snare pad on a regular snare drum stand just to get no crosstalk and set it at high sensitivity levels. This would applies perfectly even in YOUR case, where the drum brain is on the very same arm!
Regarding the side left tom: coming from acoustic drum kit, I just can say that what I've seen until now on the left are three things:
- A second snare drum (usually a "piccolo" or some "special" snare drum suitable as a 'second' voice)
- A floor tom or anyway a deeper tom, usually used to get some extra low hits made to deepen the snare sound (in conjunction) or to add hits with your left hand, that is 'out' of the usual "two-four" bar schemes
- A special effect (Octobans, gong drum, special electronic effect, etc)
This depends heavily on the musical genre you play with your band...
Hope that helps