Catguy, while I can certainly understand that you a very cautious person and weary about having a company take advantage of you. You need to consider that the companies (Indie or AAA) out there are equally as cautious and weary.
Your thought process, such as "I only work with people who impress me" and "I am hesitant to babysit a client", "An NDA makes me think you value your business more than you value me", simply put that is a very one-sided way of thinking. Whether you work for yourself or someone else, you always need to keep in mind that the work you do must be mutually beneficial. I.e. you are getting paid, are able to expand and have creative freedom, etc. but also that the work you do benefits your employer, contractor, or whomever it is you are working for.
If your only consideration is "how will this benefit me", then I really don't see how that type of person could become successful. But that is just me and my philosophy.
That's the thing though -- I help out and provide value and benefits to teams
for a living. That's my job. I am not alone in this perspective - Most people who have become capable enough to make good game code or art do it professionally. So you have to consider: What does your team offer that's better than all of the teams who offer money?
We're talking about you trying to convince someone to donate thousands and thousands of dollars worth of their time to you. Do not underestimate how much you're asking for.
A little bit more advice before I part from this thread:
You stated you can write and make greybox/placeholder 3d art, and want to make the game in unreal. Those are almost all of the skills you need to start making the game. Both Unreal4 and Unity5 (which offers very a similar rendering/visual engine) provide relatively low barrier-for entry ways to start coding your game.
Make it and as progress accumulates you will be able to recruit people who are capable.