That's a very interesting article, and I agree with what you've been saying here. Allow me to give you some interpretations (I hope these don't offend anyone):

Heavy feeler: Someone who lets their emotions run free, including outwardly. Their emotions guide almost everything they say/do, and they have little desire to expand into unbiased territory. When asked why they think something, their most prominent method of reasoning will be something like, "Because, it'll be fun!" or "Because, it's just wrong." To sum it up: Emotions come naturally and abundantly. Has to be reminded to use objective logic and might not see a reason for it. Thinking purely objectively seems harsh and inhuman.

Heavy thinker: Someone who doesn't understand why people can't give them a "real" reason for something. They find themselves saying, "But I don't need to go because (insert logical reason here)." Ceremonies and holidays aren't really enjoyed for the "emotion and meaning" that they're based off of, they're enjoyed because of the free food, presents, getting vacation from work/school, seeing relatives, etc. To sum it up: Naturally sees everything from a multi sided objective view. Has to remind themselves to show compassion towards people and might never feel comfortable showing strong emotions. Feeling empathy is foreign.

I also have a problem with "ruled by their head instead of their heart." If we did that, we'd probably have a pretty unhappy world. We'd have to have an abnormal brain or be a robot to think like that. All 16 types represent normal humans, right?

I think a better way to put it is that thinkers also have the ability to look outside themselves. That doesn't always mean they'll take the objective option though, as emotions and desires are still present, not to mention our animal instincts.

If you really want to dive into things, you could argue that living based on objective logic still results in doing what makes you happy. Technically, ignoring our emotions is NOT logical because emotions are a part of nature that is objectively there. In order to keep everything in balance, we have to include emotion into the mix when making decisions. It's like shooting deadly asteroids that threaten to hit the earth and make us miserable. The universe has no feelings; it doesn't care if 1 asteroid gets blown up, but we would care. Therefore, the logical decision is to destroy the asteroid (bad example because I don't know how destroying the asteroid would affect humanity/other civilizations long term, but let's just ignore that). That was ultimately decided using objective logic, yet emotions were still included. Based on that, making decisions using emotion is NOT always illogical.