Again, it's not micro-services the buzz word. It's easier to have different services that are logically separable - say, push notification services - pulled out of the main app. Testing, maintenance, etc., are much simpler.
Of course certain services have to be aware of others, but they don't necessarily need to be aware of other copies of themselves behind the same LB.
But yes, currently, everything is just parallel instances.
Then your problem is embarrassingly parallel and your solution does not need to be "micro services" to scale.
Sorry if I missed something, I skimmed your text.