I'm probably better placed than Beat to help as I'm using Pro Tools (I think Beat uses Cubase). It sounds to me as though you'll probably be better off using just the VI plug-in at least for now. First of all you'll need to learn how to use it anyway as VE uses it - it acts as a kind of submixer for various VIs. Personally I've not had any stability problems in PT with the VI when using up to around 16 instances, although yes, Maya's right that VE seems to handle larger counts than individual VIs. Horses for courses, basically!
Unfortunately right now I've got the small matter of earning a living to attend to, so I'll get back to you in more detail later.
For the moment I'd suggest you play around with using the VIs on their own, get used to how it all works and then once you've mastered that give VE a go and see if it suits you better or not. Basically the best way to use the individual VIs is with Instrument tracks in PT. Create one Instrument track for each VI, that way you don't need extra MIDI tracks, you just record onto each track for that instrument. I've certainly had no trouble at all with 16 VI Instrument tracks - although I have PT|HD1 which means that the TDM hardware is handling at least some stuff that's down to the host computer on your system. But I'd've thought PTLE would also be able to handle this pretty comfortably.
Anyway, more to follow. Feel free to e-mail me privately if you like.
Regards
Nick
Mac Mini M2 16Gb RAM 500Gb int. SSD 2Tb ext. SSD Pro Tools/Mixbus An awful lot of VI, Synchron-ised and Synchron libraries, amongst others. VSL user since 2003.