Having the ability to pack jobs/tasks onto the same "resource" (underlying server/EC2 instance)

This is essentially a "queue". Basically a queue is a way to abstract a specific type of resource, so that you can achieve exactly what you descibed.

open up a streaming use case, wherein batch (offline) inference could be done directly inside of a ClearML pipeline in reaction to an event/trigger (like new data landing in your data lake).

Yes, that's exactly how clearml is designed, am I missing something here @<1541954607595393024:profile|BattyCrocodile47> ?
That said if you are thinking multi-node load-balancing for streaming request processing, then you should take a look at clearml-serving,