Hi,
yes it would be a nice feature. But i will not implement it. LTN-C is solely an UI and its not meant to add features to LTN. Especially this feature would require quite a lot of logic. You could ask Optera to implement such a feature, but i don't see it coming.
There are a few things you can do however:
1. If you request liquids and items: Use stack threshold and normal threshold at the same time. The Liquid gets delivered by the normal threshold, items via stack threshold
2. You can use combinators to enable 1 of many LTN-Cs depending on what you need.
cheers