Writing? In too deep

A main goal for this year was to pitch an idea to a publisher- I reached out and pestered both Stephen Mooney and PJ Holden, two incredible comic artists with their names attached to some creator-owned properties that are well worth checking out. They shared some invaluable information with me and answered all my questions and I'm sure they're wondering what that was all about as it's been months and months since then and I haven't shown much activity.

Since then I've slowly progressed to a full second draft of a story I've been developing for, in total, a year or so now? And like most of what I set out to do, it's a bit too ambitious but I've worked hard to lay the foundations of where I wanted to go with it and began work on the first book, which is now in its second incarnation.

The problem is, I'm beginning to hit a wall with it.
Not with writing it but with progressing on it. At this stage I feel like I'm not sure it's interesting enough.
Let me try to explain- I wrote the first draft after piecing together the elements for months and I felt pretty good about the general structure I'd presented but I knew I needed this story to be strong, it needed to hold up under fire so I gave it my critical eye and made quite a few changes to help strengthen it. I knew even that wouldn't be enough so I decided to get outsider opinion. All of this has brought me to this point- where I've gone over the script various times, I've tweaked and edited it considerably and now I don't really know where I am with it.

The closest description I can manage is that it feels like I'm in too deep- I'm too close.
To speak metaphorically, I feel like I've spent so long in each of the individual rooms, making sure everything works that I've lost perspective on how the whole house looks. Or maybe to put it another way- I've spent so long picking out just the right furnishings that they no longer seem that unique to me, I've become too familiar with seeing them. Does that make any sense?

Sharing my work at this stage(script form) isn't something I've ever been too experienced or comfortable with doing but I have shown this script to other people in an effort to gain some kind of perspective that I feel I've lost. The results were mixed, most of what I wanted to achieve with the story came across to all parties but they differed on their opinions on what was wrong, or didn't work. Some of their opinions clashed with my own and I was left to try my best to take onboard the most valid arguments and try to work with them in my second draft.

It's left me a little on the fence now, like I said- I feel too close to know if this is any good any more but I'm left feeling like I've over-worked elements I felt were fine to begin with, in an effort to appease criticism. I think the story is far better for those criticisms(crucially in some aspects)but I can't help wonder if the message will be buried under all the padding I've had to do to answer the questions.

It's a weird one.

What would a writers advice be, share it with more trusted people for opinion? Take a step back? Start over?

I've never spent so long pawing over a script, I just know I need it to be strong but now I'm not so sure if it is.

-Adam