Reddit mentions of Neewer NB-35 Adjustable 27.5"/70cm Studio Recording Microphone Suspension Boom Scissor Arm Stand with Microphone Clip + Table Mounting Clamp + Power Cable

It certainly sounds like you are doing your due diligence and research and want to get the best stream/Youtube possible from your resources. That is definitely the right mentality to have.

> I imagine that if you were to consider the actual difference between audio and visual "bang for your buck" that you'd probably find that audio enhancements provide a much better increase in quality than visual improvements per dollar spent.

This is it exactly. While visuals are very important, I do not believe they are as important as audio. If the visuals are not perfect then people will still stay and watch. However, if your audio is bad it is uncomfortable and people will leave. As weird as it seems, people are more interested in the streamer/Youtuber than the actual game. People will come for the game but they will stay for the commentator. So much so that they will watch videos of games they don't care about just because they like the person talking about them. Therefore, audio is even more important because that is the primary means of which you communicate with the audience.

You mentioned doing this in your living room. Since you seem to like as much information as you can, I'll give you my opinion. Mic technique is more important than the microphone you buy. A cheaper mic with good technique will sound much better than an expensive mic with poor technique. By technique I mean mic placement, mic distance, on/off axis recording, gain settings, post processing, and room acoustics. If you are streaming or recording from your living room I would be weary of room reflections, as they will make your sound very open and echo-y. i'm not saying to go buy expensive acoustic panels, but to be cognizant of that when you record or stream. For condenser microphones, the optimal mic distance is 6-8" from your mouth with a pop filter 2" from the transducer. Experiment around with this and keep in mind proximity effect as well. You can also experiment with off axis recording, but I suggest on axis for now. Make sure to point your mic directly away from background noise as much as possible (keyboards, mouse, fans, computers, etc). As for gain, I suggest setting it to about -12 dB while talking normally. Then be really loud and see if your mic clips. If it does, turn down the gain a bit. This is called head room, and it keeps your mic from clipping and distorting. For post production (for Youtube) I suggest looking at Normalizing and Compressing your audio as well as applying a Noise Removal.

If you go the XLR route, I suggest the AT2020 ($100) and the Behringer Xenyx 802 USB ($80). Get a pop filter, shock mount, and a desk mount. I have the neewer and it works great. Since space is a concern (being in your living room) you can fold the desk stand out of the way when you are not using it. The board isn't all that big, and looks really nice and professional on your desk (people will comment on it all the time).

Hope this helps and gives you a few things to think about! Here's My Setup if you are interested. I do not recommend the Alesis board, I wish I would have got the Behringer (they were out of stock in my area and I didn't want to wait).