As I've repeated multiple times, the entire reason for this is due to the fact 1U should be the highest non-banlist. Forcing GSC OU to be 1U if GSC Ubers is a proper tier (which you even stated should be a main tier) is blatant favoritism, and goes against the precedent set by PP ORAS. As stated above, while likely more limited compared to GSC OU, GSC Ubers is very possibly more versatile than RBY OU, our 1U for RBY. I may be wrong, but forcing GSC OU solely because of tradition and diversity's sake goes against how we've been setting up Pokemon Perfect's tiering.
Addionally, everything I've seen and heard suggests GSC OU in its current form is very rarely played outside of Pokemon Perfect, which to me further lessens the need to enforce GSC OU as the standard.
I feel the only unbiased way to determine whether GSC Ubers should be 1U is to focus solely on Ubers as a tier ignoring all established GSC tiers. By itself, is it a proper tier? Does it have a sufficient amount of viable Pokemon and strategies? Most of all, is it fun? That is something I was hoping there would be more discussion of when I posted this thread. If the answer is yes, why other than our biases would we claim it is not suitable for 1U? If the answer is no, then it is not suitable for 1U, and that's that.
From everything we've discussed though, if GSC Ubers became 1U and GSC OU became 2A, they would be co-main tiers with the only main difference being GSC Ubers having the '1U' title and determining lower tiers.
"As such I feel like more to gain by having GSC OU, which is more diverse and skill based, be the main tier."
Considering GSC Ubers has not been fully explored, that's quite subjective. Not only that, but a very poor argument to make GSC OU our 1U. If ADV XU was more diverse and skill based than ADV OU, should it become 1U? Again, GSC OU should be 1U in the case that GSC Ubers is not suitable, not an arbitrary judgement on 'diversity and skill'.
"These are just my primary thoughts on this issue. I want to say a bit more on the issue of letting ubers be the main tier but that is best saved for a different time I feel."
No time like the present! We need discussion on this, especially before GSC 1U is determined. If we establish GSC OU as 1U, then later decide "Okay, now we might want to discuss GSC Ubers", there would be heavy resistance atleast because of the work of starting over. This needs to be examined before anything is set in stone.
The Borat quote above I feel does a good job of describing this: "the requirements to keeping something the same is much lower than the requirements for change, and that's ok, that's how life is. look at how hard it is to amend the constitution. look at how difficult it is to get faster internet in the us - the initial 768kbps definition for dsl is totally arbitrary, look how retardedly hard it is to change that."
In regards to the viability list, that's why I repeatedly mentioned it was 'incomplete' (I guess that didn't exactly mean what I'd meant, can't think of a better word for it right now.) Your list makes a good starting point, but I definitely want to get proper rankings for it. I gathered that it wasn't to Pokemon Perfect scale, and is probably more like A=A-B, B=B-C, and C=C-F. From what I've seen, every Pokemon B rank or higher would be very likely candidates for viable Pokemon and atleast C Rank or above in proper rankings and be serious choices for teams.