George Duke, thank you for the comments.  I just wanted to add a few things in response:
1. I think you are getting the idea of what is attempted here.  I believe starting with a few, and then growing to 25 works.  
2. The Seirawan drop (version of gating) is as you described.  It is one of the least disruptive versions and a natural evolution in chess.  In addition, it provides a way to get more piece into chess.  Other attempts, outside of a limited zone drop into start areas (at start or during the game), doesn't expand the opening book, causes the initial piece balance of pieces to change, or changes the initial pawn structure.  When you go to a larger board, you end up with the complaints about the knight losing power, pawns unprotected, or being forced to deal with the name that shall not be named, for legal reasons.  The larger boards also don't add a way to make chess expandable. either, although it extend the life of chess.  Drop and gating ends up making for a way to bring new pieces into just about into chess, in the least disruptive way.
3. I am of the belief that the consensus method, which is an evolutionary one, determined from a lot of play is the best at making changes.  It is how chess managed to grow and evolve over time, surviving the migration to mad queen.  Other methods force things, and aren't natural.
4. I am not going to say a static/fixed opening lacks creativity.  What I will say is that it creates a community that is used to a fixed configuration, and makes it hard to adapt to any needed changes, although changes can happen and does buy you a bunch of times (a few hundred years maybe).  The fixed position in chess results in any changes to chess now being marginal.  There is no smooth way to experiment and while keeping the foundation in order.  I believe gating and drops, even if restricted a lot of ways, offer a chance to do this.  Even if such is used before game begins, it helps.  Let's just say that Chess960 is in the drop family, for example.  It is just that where the pieces are dropped occur before the game begins, and not in the control of the players (done at random).
5. I know people might be upset about the whole 8x8 board as a start.  This is done for pragmatic reasons.  It doesn't mean you only have to use that board, but it makes it easier to get people to migrate over as a starting point.  What is looking to be done with IAGO Chess is to allow a variant class to have larger boards and so on.  As for there being 9x10 of Chinese Chess, and 9x9 of Shogi, I will say the IAGO Framework can work with these games to create an IAGO Chinese Chess and an IAGO Shogi.
6. IAGO stands for International Abstract Games Organization.  It is mean to give all abstract strategy games that don't have an association for them a home, and coordinate efforts between games that do.  This whole Capablanca on the 8x8 board came about due to issues it ran into looking at ways to do Capablanca chess, and finding out there was rejection on the Seirawan chess people to have anything to do with the IAGO World Tour, and the chess variants community.
7. Yes, I have mixed feelings about Seirawan chess.  I like the game alot.  I believe that it could serve as a foundation for a LOT of chess variants and be a basis for a migration path for chess.  However, the word from the Seirawan chess people was 'get lost and keep your chess variants away', so it was time to move on.  End result is you see an interest in Seirawan chess, but also the idea to be similar to Seirawan, but friendly to variants and also provide a migration path and frameworks for chess to evolve and bring all variants into IAGO. 

Let me sum up the one new rule brought into Chess via IAGO Chess: Thou shall have your piece mix match up with the rules, and not force people to flip a rook and then require it to be a queen only (gee, what happens if someone wants 3 knights on the board?).  There are other elements in the base rules, that are recommended, but mutable for variants.

If you want to see the rules to IAGO Chess, they are up on chess variants, and can be found here:
http://www.chessvariants.org/index/msdisplay.php?itemid=MSiagochesssyste

Feedback is definitely welcome, as is playtesting so we can make tweaks as needed.  I suggest people start off with B-Class or C-Class rules first, before doing tweaks.  I am hoping to get a Zillion adaptation done soon for this.  Need to figure out how to do the gating for the game.