Yes, there are a lot of internal dialogue scenes like that. A lot of them. And on all of them my point remains the same, they are all the same thing.
And I dont' even remember the moments he tries to reach out to anybody to be honest, and I've played up through disc 3 of this game twice, the second time was me trying to force myself to finish it years later. Perhaps these scenes do exist, but if so then they basically get completely overshadows by everything else squall does.
And its not that I felt it's not how it should have been done, it's that they did it horribly regardless. The moments of developement with his party members you mentioned get completely overshadows by his complete and total one sided personality, and after his change of heart, he doesn't even seem like the same character anymore.
I would have been just as pissed with a gradual change, if he started teh same and ended up a colorful circus clown obsessed with Lemon pudding. THe fact is, he wasn't the same character at that point, at all. Nothing outside of his appearance felt like it was still squall.
Admittedly I might have missed out on some things as you mentioned, but it was still so horribly done and overshadowed, it doesn't really matter if he has character development or not, it was still terribly done.
And on the note of Amarant, he isn't an ass to you because of what you did. He simply knows you because of it. It is easy to see from the get go, being an ass is just who Amarant is.
He grabs the job upon the rumours of a tailed man yes, but thats because he wants to fight you. It has nothing to do with him being an ass.
And Amarant does in fact grow, if only a little. He may leave you in the end, but he begins to understand the reasons for working with other people. I recall you seeing him with Lani at the end, showing some growth to him. You say it has no importance, but in the very little screen time he was given, he showed, even if only a little, legit and believable development, something an entire game focused on Squall failed to do.
True, it could have been better, and I personally think more screen time could have helped, but thats beside the point.