The only thing wrong with the current format IMO is the same thing that is wrong with every guild-based aspect of the game, and that's that there are no restrictions. The same restrictions would fix GSing that would fix towering.

Players should need to be a member of a guild for a certain amount of hours before they're able to GS at the ranked spars in the Battle Arena. It completely defeats the purpose of bracket seeding in the GST if the seeding is skewered by teams recruiting anyone and everyone to help inflate (or deflate) their score, thus putting them at a seed that doesn't reflect how good they actually are, thus completely disturbing the flow of the tournament.

I've still got my fingers crossed for that one-month rule for GST participants, too. That'd turn it into an actual GST, a guild spar tournament, not a team spar tournament. Overall, would just like to see the game be more rewarding for good guilds. A team of 5 people that get together before the GST is not a good guild. A group of people that endlessly "noob recruit" to hold towers is not a good guild. Neither should be allowed IMO, and it'd improve the quality of gameplay and competition overall if they weren't.