I feel the same way, JustHer. I don't like sugar-coated fluff or vagueness, either. I like direct communication. That being said, direct communication can be tactful and diplomatic without being sugar-coated fluff.
Of course, as isfp and entj are polar opposites, there may be some difficulty in communicating well. ENTJ is a directing type and ISFPs don't like to be told what to do!!! This is where tact and diplomacy really help.
Speaking about ISFP and ENTJ, I had been having difficulty figuring out my own type. I thought that I was an ESFP so I put that in my information. When I realized that I was not an ESFP, I mentioned in my blog that my career as an ESFP was fun but short-lived and I asked for suggestions of other types that I could try out for about a week. The recommendation was ENTJ. So I put ENTJ on my information and had a lot of fun for a week pretending to be an ENTJ. I was, of course, just a caricature of an ENTJ but I had a great time. Pretending to be a (not-very-good) ENTJ did help me learn to accept ENTJs for who they are, without trying to make them be more like me!
The one thing that I really like about what you said has to do with honest communication. As an ISFP or as a (fake) ENTJ, I prefer to hear the unpleasant truth to vagueness and fluff.