What follows is written with limited knowledge of the internal workings of the balance team and whatever practices they've adopted.
This is a broad topic, so I'll keep it short--I think it would be useful to identity and define more baseline terms and concepts that can be used when discussing the strengths/weaknesses/balancing of a given unit or faction.
Consider DPS: it's a derived quality, not rigorously defined, but is a useful construct when we talk about general effectiveness.
How can we identify more useful concepts like DPS? Consider the blog on MtG R&D lingo here, and the definition for "Knob", reworked for FaF:
"Knobs – These are elements of a [unit], usually involving numbers (things like [mass cost] or [damage]), that give the [balance team] the ability to adjust a [unit] for balance purposes. The more knobs, the better for play design."
I think that's a useful concept, not only for first-line balance discussion, but also in how it makes "have all the relevant knobs and their interactions been recognized when a suggestion is made?" a straightforward method for assessing how much thought has been put into a given balance suggestion.
"Knob" is one possibility. DPS as a distribution instead of a single number is another. I'd like to hear more!