I looked over the NDA that you have and it looks fine. Pretty standard stuff. However, I would not like to be bound at this point by an NDA. As a design studio, I need the flexibility to be able to pursue a new design without having to worry that some part of it may have been shared with me by someone else. I do not have any intent to steal anyone else's designs or to pursue the kind of games we discussed in the context of your company, but nor do I want to give other people cause to think that I may have stolen their ideas when I publish games.
Game design is very very flexible. We constantly appropriate ideas from each other, learn from previous designs, innovate and improve upon what each other do. The industry and public are all better off on account of this practice, but what it requires is more ethical rather than legal restrictions. People who steal another people's design wholesale should be held legally responsible... but I personally believe that adapting or appropriating certain mechanics when they do not constitute the body of the design and they are combined in novel ways should not constitute infringement.
However, most NDAs (including this one) do not have the refinement and nuance to permit one without permitting the other. As a result, I would rather not know anything that your company is working on than be in a position where I have to worry that even the smallest aspect of what you share with me, if incorporated into a design I work on independently, would constitute infringement of your rights.
That being said, I would be happy to provide you with any amount of 'blind' advice. If you have questions that you would like me to answer about either the business, game logic or design, then I would be happy to provide you with feedback, suggestions and advice. I would also be willing to sign an agreement with you that gives you legal title to use that feedback without having to further request my permission, but my advice has to be seen as given (in legal jargon) non-exclusively and what I say to you I reserve the right to use myself. I would expect the same from you in return, and then I will let you decide on a case by case basis how much you are willing to share.
Ultimately, more can always be done when people work together and when they trust each other. So, usually an NDA is a good step in that process. But, I think that understanding what I do, what I want to do and how I do things is actually a better basis for trust than any piece of paper. I would like to give you advice and consultation free of charge. If it turns out that you would like me to do more than just advise, then I'd be happy to sign an agreement with additional confidentiality that recognizes the partnership between our two companies and keeps your information private. But, up until that point, I want to still maintain my freedom to design stuff where my mind wanders.