Random i know - and i'll preface with, "i am 100% serious about this"
I am a bit of a savant when it comes to understanding game design philosophy, what people like, what they wouldn't. I have the unique ability to know this stuff from the outset, and to be able to see the many variables that most people would require iterations of failed attempts to figure out, immediately.
What are my credentials? Don't have any per say. But not many more people in the world have played the amount or variety of games that I have, in the way I have. That is, I break them down to their core, and I 'beat' them. I don't play games, I analyze games, and have done it since I was 8.
Again, this is awkward, and I am sure this will certainly be criticized, or worse, completely ignored, but I am willing to consult...for FREE, and help you redirect any semblance of game you have into something that perfectly fits your version. And I am confidant I would be able to successfully do this with only a few hours of discussion with game devs.
Honestly ... what do you have to lose? A few hours? Hell, the worst thing you'd walk away with is just a few additional ideas.
Think about it! "Can someone really be THAT good?" who knows...maybe im not. But I loved terraria, so chances are we at least would have a good conversation.
Right, so, once again, I'm not a developer, so if they do want to contact you, they will, but personally I would advise you not to get your hopes up.
First of all, strictly from a management perspective, you would have to sign at the very least an NDA in which you contractually oblige not to disclose any of the unrevealed content shared with you. Writing one, signing one, and potentially taking legal action if one turns out to be breached take
a lot of time, far more than mere insights are likely to be worth (as opposed to, say, actual content creating or Q/A work). Of course I'm not saying that I think you have malicious intent, but assuming you have no previous relations with Re-Logic, that's an option they at the very least have to consider.
Secondly, you are far from the only person who has (or more accurately, would) offered this. If they offer you this opportunity, they would have to offer it to everyone, lest it be 'not fair'. If they do indeed hire people for consultancy work (which I highly doubt they do), they would be more likely to work with people who specialise in that kind of work, and actually do have those credentials you admit to lacking. I'm not saying you don't know what you're doing, it's just that hiring someone who can prove that is a safer bet.
Thirdly, and don't take offence to this, but I don't think they really need you: analysing games is something most (if not all) game designers are capable of, and I would even go as far to say that most people who are only passively interested in game design (or even just games in general) are. Even if you are as good as you say and could skip a few loops in the iterative design process, the developers of Terraria: Otherworld have already proven themselves (that is, Re-Logic to us, and Pipeworks at the very least enough that Re-Logic took them on board) to an extent that I think we can trust them to make the right decisions eventually, if not immediately. Re-Logic in particular already have shown they are
really not willing to cut corners on the design front, even if it means substantial delays, so I think the quality of Terraria: Otherworld is very much secure.
You are of course always welcome to make suggestions in the
Terraria: Otherworld Suggestions & Ideas subforum (as I see you already have), and if you are really confident in your design skills, you could always become a game developer yourself, but I highly doubt that a private, in depth consultation scenario where you actually get to influence the design proces of Terraria: Otherworld is at all likely.