That doesn't sound as useful to me as the others do. Like the Turrets, the mines, the Weapon Buff etc
If I upgrade a Supply CP, our entire team gets another supply pip
in addition to the original pip granted by that CP, meaning you as a Medic can heal/buff someone an additional time, Soldiers can pass out more ammo; Engineers can pass out more upgrades.
If I upgrade a Health CP, our entire team gets another health pip
in addition to the original pip granted by that CP
and any buffs we may have from our character or our friendly neighborhood Medic.
The effect of the Upgrade may not be nearly as immediately visible or as damaging/dangerous as turrets, mines, or a golden gun, but it could very possibly give the team that controls the Health CP the durability to outlast the enemy in a full-blown firefight, and the team that controls the Supply CP the ability to buff each other more often, giving them an edge in that same full-blown firefight so long as they play selflessly (imagine the havoc an entire team with all eight players having Health Buffs, Weapon Buffs, and Incendiary Ammo could wreak on the opposing team).
Not as immediately visible, no. Not as useful? I very much disagree.