1. Yes having a bigger diversity of units available can be an advantage (if you know how to handle them).
2. On the other hand: The more variety you have, the longer it takes to get used to each unit.
3. Aside from that. More expensive units or units with more stars to unlock are not automatically better.
There was a different topic a while ago where someone had problems countering a marder-rush with his MBTs.
Conclusion of that: His MBTs where oversized for the job. So instead he got light tanks that where only slightly stronger than the marders. However they where much cheaper, so he could get more of them.This game is all about using the right tool for the job. Get units that are as expensive as necessary, but as cheap as possible.
In some situations, a cheap 20-resource unit from your starter deck can be incredibly more useful than that fancy ~200 point MBT that you've just unlocked.
And dont tell me resource-cost isn't important.: The more expensive the units you field, the more you risk loosing and the faster your enemy will acumulate enough points to win.
To sum it up... having a way to see the amount of stars someone has wouldn't hurt, but only because of this:
Yes having a bigger diversity of units available can be an advantage
The OP still totally exaggerated the impact of command-star-unlocks, which I think was the main reason for all those harsh responses.