When you say lacking...can you tell me if there is a feeling assoc. with this? This helps me to understand what may be happening with ISFP's and their need to experience...that is, if indeed it is Se. I just don't do well with this type and your words are very interesting to me...I'm aware of a sort of meter, too. If I don't sometimes do this stop-and-stare thing, it feels like something is lacking. And when I do do the stop-and-stare, then after a while the meter is on full and I can go home satisfied.
Also, since your tertiary function would be Fi, have you experienced what you feel this is? If so, can you explain anything from your vantage point. Your ability to put into words what an Fi dom has trouble with, could go a long way to helping..
Thanks for your thoughts.