Ruling entrust out because that would be too obvious, they can be useful in some situations that come to mind:
1) When you're way above the attack cap for the current target and you don't need defensive stuff.
For instance let's say you have lotsa buffs from multiple sources and are using Frailty as one of your two bubbles. In such a situation using Fury would produce no result, but using STR might increase damage a bit. STR is an example, it could be any stat, for instance INT if you're in a Mage pt.
2) When you are not allowed to use debuff bubbles (Malaise, Frailty etc) or they have greatly reduced potency on the current target. For melee pts you could go with Fury/STR for instance. or Acumen/INT for mages, and so on.
3) You have two GEOs in pt and the second GEO is out of options because the first one already used the important bubbles to increase damage.
Lol. But I haven't run into such a scenario in years honestly.
When you don't have these specific situations, you're far from the attack cap or you could benefit from defensive bubbles, then I'd rather go for one of those before I use one of the Stat-enhancing bubbles.