Since you brought up the original Toronto workshop version of the show, I should mention that I watched it on YouTube (it's in three parts, called "Seussical slime tutorial" or something) and I really didn't care for it.
I know it was a work-in-progress, but there was so much that didn't work about it compared to the Broadway show. Among the things I personally disliked (aside from Schmitz being a villain)...
A lot of the songs were clunkier ("It's Possible" was much longer)
There were no costumes or sets at all (I've probably said this before, but I really don't think the minimalist look that the creators insisted on was a good idea)
There was an extremely long musical number with Mayzie in Palm Beach that wasn't needed
Jojo didn't reunite with his parents until the climax when the jungle animals are trying to boil the speck, so the reunion is incredibly rushed and lacks the emotional punch of the reunion at the end of "Havin' a Hunch"
Speaking of which, "Havin' a Hunch" was a completely pointless number since it didn't help Jojo get home. It just started up... and then stopped. Granted, this was a problem that extended to the Boston version as well, and wasn't fixed until they cut the Lorax song from the Broadway version and reworked it
We didn't get as much focus on Horton and Jojo's friendship. Not just because we don't have the touching reprise of "Alone in the Universe" just before "Havin' a Hunch", I don't think Horton even mentions Jojo for a long stretch of the play...
I dunno, I've frequently seen folks involved in the play talk about how great the Toronto workshop was and how the Broadway show removed so much about it that worked... and I'm just not seeing it. I think most of the changes made for Broadway were for the best.
I'll share my opinions on each of your points.
The songs being longer. Yeah, I understand what you mean there. Big instrumental breaks with no dialogue can get a little boring at times.
No costumes or sets. Again, agreed! Half the fun of Seuss's books are his colorful, whimsical illustrations!
A Lazy Day in Palm Beach. As much as my friends on the Seussical Discord server seem to like this one, I'm not much of a fan. So again, I agree.
JoJo not reuniting with his parents (or any of the other Whos) until later on. To tell the truth, this is actually an element I enjoyed, but more specifically in the Boston version, because we see Schmitz as the first one to help JoJo down from the balloon he floats into the town square on. I literally had to rewatch the video three to four times to make sure it was Schmitz helping him down and not one of the cadets! Oh, well. At least we have all the additions of Schmitz greeting or thanking JoJo that later stage productions have made (some of which you can see here).
Havin' a Hunch being a pointless song if the Lorax number is there. YES. This is a very unfortunate truth, and I'm saying this as someone who used to defend the Lorax number just for the sake of the scene with Schmitz from the Boston version I described to you.
Not as much focus on Horton and JoJo as friends. Well, to be fair, in the established musical, they don't really talk too much outside of that one scene (or those two scenes, if the reprise of Alone in the Universe is included), and they didn't know each other at all by name in the original book. But I can understand how you feel, given that they definitely do love each other as friends.
I was indeed thinking of adding one or two elements of the past drafts to my "film script", but none of them are these. I'm glad you agree with me on a lot of these points, even if not all of them, and I respect your opinions on the ones we disagree on. Broadway Seussical for the win!