Well I've always enjoyed GLD's cure. I mean by itself it is weak... but when you use it WITH GLD's strong mitigation tools the effect HP from that small cure skyrockets.

To illustrate the point. Lets say you have a boss that hits for 1000 damage. And a Tank who can heal for 200 HP.
You are still taking 800 damage.

But then that tank activates Shield Oath. So that 1000 damage becomes 800.
That 200 cure brings it down to 600 damage.

And then the tank lands Rage of Halone. Tank is only taking 30% damage. That is now 700 damage.
That 200 cure brings it down to 500.

And now the tank uses Rampart. That 1000 damage is now 500 damage.
That 200 cure brings it down to 300 damage.

And then the tank hits sentinel. Mitigating an impressive 700 damage to only take 300 damage.
For those 10 seconds that cure goes from healing a measly 20% of damage received to a whopping 66.6%. Bringing that 300 damage down to 100.

So the principle is the stronger your mitigation the stronger the effective HP of your cures is going to be. If spam them thinking you are going to accomplish something, then yes you are right, they suck. But if you use them sparingly WITH your cooldowns that 'little cure' can go a lot further than most would think at face value.