Thanks for your post, Fightingdragon! I'll try to give you some ideas of my perspectives on them:
1.) 3.g3 is not dangerous for Black. If White does not do the c4 try, he can equalize easily, and even after c4, if he castles short quickly he has no problems, as you mentioned. There is a game, I think it was Razuvayev - Skembris, where Black got a crushing position with normal moves from both sides.
2.) No advantage at all for White. Is White better (in rating), Black makes a draw, if White is worse, Black wins.
3.) Still not much practice with that, but after some analysis with some of my clubmates no fear so far.
4.) I like that one, too. Had a nice game in the Norwegian League with it.
5.) If you play 7...Nf6 and 8...e4, you get a nice position where White often does not know what to do. Also beat some players with it, even had GMs on the brink of a loss (in tournament games that is, blitz games are another story, in a positive way

).
6.) Yes, Bronznik and I made some improvements in this line. They can be seen in his second edition of his Chigorin Book.
7.) The "Four Knights" is even better for Black if White plays the "normal" system played in the former critical game Georgiev - Morozevich. Black can play 10...Bxf3! and obtain a very nice game. White must try something else here.
8.) I don't like this line at all for White. Black has promising play anywhere (I prefer ...Qh5).
9.) I concur, Black should be ok. And fun positions with many tactical tricks, too!
10.) Had a game against GM Nyback, which went quite well. Will post it later (if I get home)
11.) I agree.
For your thoughts on the line with 4.Nc3, cxd5 and Bf4 ... I played a game as Black against Epishin (who you mentioned) in Kiel last year. After 13.f4 I think I played 13...g6 and chose a setup ...Nc6-d8-e6 (BEFORE castling queenside), 0-0-0 and then followed up by ...g5 at some point. It is in my opinion quite promosing, since White hardly has any prospects on the queen side. In our game, Epishin transferred the Knight to e5, but that took too much time. I could generate counterplay with ...g5 (pressure on h2, g-file) but eventually lost after I got too cocky. I will try to post this game as well
And for the lines with 5.Bg5 or 5.cxd5 exd5 6.Bg5, I have a nice game for you as well, which I played against Plüg in 2003. The secret is to trade the Bishop against the Knight at the right time and play ...f7-f5. The white bishop will be weak then and Black has good attacking chances on the queenside. I will post everything when I get home tomorrow...
hm, but now off to breakfast