Victorious, I and a few others have been working on a system for handling commercial titles, and may be able to help you out once you get far enough along.  We currently have both C and BGT interfaces.  It does require network access for most of its authorization, as there's not really any other way to have solid piracy protection.

Frankly, in this day and age, there's really no excuse to not have network access.  Sure, outages happen, and we've been setting things up to allow for a temporary offline mode - but I'm convinced that the vast majority of people demanding offline versions are either confused or want a standalone version that can be cracked.

-dentin

Alter Aeon MUD
http://www.alteraeon.com

@Victorious, you mentioned needing full 3D sound, and that meaning you need HRTF.
Just to clarify, there are many 3D audio libraries that do provide 3D positioning of sound via panning, volume, and low pass filters for things behind you, but do not include HRTF.
And I've even seen Aprone and CAE Jones discussing the algorithms they use to set panning and volume adjustment to avoid the need for a separate 3D audio library at all.

So I'm just saying that HRTF makes it sound better, and is a nice to have, but for your first 3D game it is not a requirement.
Swamp is a good example of a successful game doing 3D audio without HRTF or environmental reverb.

My opinion on the performance of C++ versus C# is that it is negligible for audio games.
I also think C#, (and other high level languages), are considerably easier to learn and use than C++.

Programs written in C# are definitely easier to reverse engineer than those written in C or C++.
I guess you have to weigh the importance of this along with the other pros and cons of both languages.
For me, and admittedly I focus on free games, it is not very important as compared with other factors.
If you charge for an online game then the reverse engineering aspect matters less as online content and user accounts become most of your protection.
And as Camlorn said, writing it in C/C++ does not stop people from cracking it.  It just raises the difficulty level for doing so.
And only one person needs the expertise and motivation to crack it, then they can just share the crack.

I use C# in Visual Studio 2010.
The debugger is not accessible, but I can still use it because I used it when I had more vision and I am familiar with the hot keys and some extra steps I need to do to get the information I want from the watch window.
That said, I actually don't use the debugger and instead rely on logging, which can be nicer when debugging a game that is trying to run at 60 frames a second and you want to get useful information, but not stop the game from running.
And despite some of visual studio's annoyances I actually love features like go to definition, auto complete, rename symbol, find all references, extract method, go to file and line for this error, collapse/expand method bodies, etc.

I heard Microsoft recently released Visual Studio 2013 Community Edition, which is like the Professional edition, but free.
I haven't tested it's accessibility though.

All this is just my 2 cents.
Obviously you should make the decision about which language to use.
And even though I have a preference, I really believe that you can write great software in pretty much any language.

no no no. I'm not saying that you should make one, just that it can be done in about a day assuming all the other parts exist and you know what you're doing.  There's a lot more to a good audio experience that takes longer, i.e. reverb, and of course all the other parts have to be there.  The irony is that, if you know the trig to compute the parameters, the part that applies the effect itself is about 15 lines.  It's all the stupid framework and support code that gets in the way.
The problem is, at the moment, that's the easiest way to get it in my opinion.  OpenAL actually graduated to tortuous today when I found yet another shortcoming in it, and distributing OpenAL and managing to get a consistent experience is next to impossible without instructing users to edit an ini.  Long and short of it is-no, you don't want HRTF for your first game.  You can get away without even lowpass.  if you've never done a game or medium to large programming project of 2000 lines or more yet, don't bother and just use the most basic thing you can find.

The service model is intended to be similar to that of steam.  There's a master controller which runs all the time and talks to the server as well as to any games you're playing.  Games get permissions from the master controller and can verify those permissions via the web.  Games will also be able to store unlock state on the server, so if someone unlocks a secret level it stays unlocked if the player logs in on a different machine.  We'll also handle the purchasing and financials.  Our goal is to provide a distribution service that takes care of the distribution, protection, and financial issues so game developers can actually spend their time making games.

-dentin

Alter Aeon MUD
http://www.alteraeon.com

@Dentin: how much will your steam platform charge for usage? I'd assume that its some percent of sales.

Is the AccessibleOutput2 library usable in other languages besides Python?

Is there a less painful way of adding a library to a project in visual studio 2013?