I hope you don't find my comments to be insulting in anyway Chip, as my aim is to provide support and advice, which may be subjective, but there is reasoning behind it :)
When I said about there been no connection, I meant that the characters don't feel like they are in the same movie as there is no interaction and the interaction that does exist is quite muddled. If you look at the original poster for The Little Mermaid you can quickly understand that the two main characters are in love, their friends are supporting/ happy for her, but their situation is under threat from the two characters at the top of the poster. The one on the right has very cool colors and evil features so we know she is the baddie and the one on the left looks angry, but we can tell that he is a king and he has a very warm presence.
You do have some of these elements in your poster, but it feels more like they have been put in with less thought. If I look at the characters in your poster I can understand that there are 2 baddies (although there may be 4 due to the arms coming into the frame). When I look at the 4 princesses i'm not sure why Ariel is looking to the left of the frame or why is sleeping beauty looking at Ariel in a seductive way. Also, why is there a snowman and a monkey? Is this going to be set in a desert or the Arctic? Does the monkey have a thing for the octopus and is the snowman happy that Ursula is in control? These are things that will confuse the reader. I do like what you have done with the 2 characters in the middle of the Ursula's tentacles and perhaps it might be better to push that, and use that idea of control and being trapped as the main theme.
I did a super quick sketch of something different from the stack of faces, using your idea of having the princess trapped by the tentacles, as the other princesses are protecting the new one in the middle, you could even have olaf and abu ready to fight to make it more comedic. You could also put symbols of the evil objects in the background, but more as an easter egg rather than just to say "hey look at this object from this movie or this from this movie". Of course it is more of a teaser poster and it's not as warm as a kid's movie should be, but I hope you get the idea of trying to tell the story through the poster is a better way then stacking up characters (not that it doesn't work, but it has to have a meaning behind it)
You mentioned that you used the last jedi as an inspiration for the poster, but that is telling a very different story, also tbh I think that that style of poster is quite lazy in terms of design as are many modern posters. If you look at the original star wars poster it tells a story by itself. Luke and Leia are the brightness in the dark that is controlled by the big scary helmet guy. Of course that's a matter of taste, but it's important to know what the poster is suppose to tell