Balancing two options by multiple opposing arguments, alternatives to "on the one hand ... on the other hand"

Solution 1:

Balancing already suggests scales, so even your home language metaphor is redundant. Similarly, you don't need any hands at all:

The most profitable inventory level requires balancing [this] against [that].

The most profitable inventory level requires balancing losses in storage costs, product obsolescence, and capital employed against lost sales opportunities due to insufficient product availability.

Your [this] and [that], though, complicate the sentence. Maybe you can tighten things up a bit (and move capital employed so employed doesn't try to be a verb):

The most profitable inventory level requires balancing storage cost losses, capital employed, and product obsolescence against lost sales due to insufficient inventory.

Finally, I think this is what you're actually trying to say:

Finding the most profitable inventory level requires weighing storage cost losses, capital employed, and product obsolescence against lost sales due to insufficient inventory.