I may come under a lot of fire for this view, but I'll share it anyway (it's never stopped me before!) - Also, Dave, if you're reading this, I'd actually really value your opinion on it too.
The answer (if there is one) depends a lot on what the current goals of the ASR actually are. I'll suggest 4 possibilities, but I'm sure there are lots more:
1) A good excuse to play lots of games with a competitive feel
If this is the goal, reviews should be optional, and games should probably be a lot shorter, perhaps 10 mins + 5x0:20 byo. I'll keep this one short as I don't think anyone quite feels this is "the priority", but as daal mentioned the goal was playing lots of games (even though I'm sure this wasn't what he was implying) I thought I'd mention it.
2) A friendly environment to play and learn
By and large, the ASR seems a pretty friendly place, and it has its own KGS room, website, and forum (albeit here on L19). However, there's not a great deal of social interaction, and there isn't much ASR focus on making more happen. The number of players that participate on the forum is a tiny fraction, and the website has little access or social use, instead being used for rules, guidelines, hints and tips, and the league results.
The games have sensible time controls for learning and playing, and reviews are recommended at the end of the game, which helps in some respects to learning. However, I think if 2) is the goal, not enough is being done to encourage an interactive community that could interact explicitly on teaching and learning material as well as general social interaction. For example, threads in a dedicated ASR forum that are dedicated to studying josekis / fusekis, analysing when tesujis work and when they don't, regular L+D challenge problems for different levels etc. This would seem like a consistent way to develop further in the future, but finding a way of combining the existing league system successfully could be tricky.
3) A serious competition environment, with emphasis on learning as a side
I think this is probably the closest of the 4 goals with respect to how the ASR currently functions in practice. The games are suitably long, reviews are advocated by the administration, and the league system rewards both activity and performance. There's incentive to play games, and incentive to win, and I think that the league achieves 3) pretty well.
An enhanced online presence, perhaps on "featured games", or "featured players" might be interesting, with interviews (including questions on how to improve the league!) of some of the more active players. Stats would also be nice for many I think (total games played, total games won, total points earned, perhaps with the ability to break down both by tier and by month), as most competitive environments seem to benefit from this kind of thing (too many gamers are stats/numbers afficionados, especially in the Go world). It would also be possible to keep an "ASR performance rating" running alongside it with ELO evaluations of the players, so just as with the chess world, there'd by the champion (by competition), and the highest rated player (by overall performance), who are not necessarily the same.
4) A serious learning environment, with emphasis on competition as a side
I think this is probably the closest of the 4 with respect to ASR's officially stated goals. If the goal is to help players improve first, and offer a competitive environment second, I think there are a few ways of improving the current system.
As someone who has successfully taught quite a few students, I would have said that the greater the investment (in money, time, energy and/or stress), the greater the potential gain in ability. The more you invest into your improvement, the more focus you have, the more stress you have, and the more you remember of the pros and cons of your play and your opponent's play. If I was to have lots of time and money, so that I could play in the ASR (unrated), on KGS generally (for rated games), and paid tuition (with teachers), my concentration, focus and effort would be 1) teacher games, 2) KGS rated games, and quite a long way behind it, 3) ASR games. If we are genuinely keen on using the ASR as a platform for improvement in playing ability, this order seems somewhat perverse. I actually believe that, whilst playing stronger players and having them review is awesome and useful, simply playing long, serious, highly focused games against the same level opposition and reviewing it together afterwards can be really effective for improving and learning.
Rated games are more stressful, it's easier to make excuses to not play, and I feel 100% sure the ASR would lose a bunch of players, and a bunch of games per month if it was implemented. I also feel 100% sure that those that remain would focus harder, put in more energy effort, and have less need to play rated games in the EGR (allowing more time to focus on ASR games). I think this would help players to improve their play considerably more, and if 4) is the goal of the ASR, I think rated games makes much more sense than unrated games. Alex has taken a different route with the Insei league, and gets people's motivation and focus based on paying money, but I think making games rated will be more effective, and easier to find the players who feel in a position to play in the system. As with 2), the focus for online development would probably be ideally related around discussions of study material - the ability to post positions, moves, games, ideas, and discuss them, as well as in-depth analysis and ideas behind josekis and fusekis.
In summary, I actually don't feel particularly strongly, as it depends entirely on what the ASR feels is its goal. When I first joined, I was enamoured by the idea that this "wasn't just another league". The goal was a competitive environment (which I love), with serious games (which I love), and first and foremost an opportunity to really improve your game of Go. If the latter is now less of a priority than the former, "serious games" becomes "longer games" (which I love slightly less
), and much of the unique appeal it held for me disappears. I could go join the BGA individual league instead (where I know most of the players, so get a sense of community from it) if I wanted to simply have a competition with other Go players. On the other hand, if other people want it, and more importantly if the ASR administration feel that the competition should be the core of the ASR, then it's the right decision. However, trying to achieve both 3) and 4) equally I think will leave the ASR doing neither thing outstandingly well, which is worse than focusing properly on one of the two aims individually.
PS Anecdotal evidence of one: I'm a [-] player and it would bring me _back_
I just didn't want to speak for them, since it would be rather self-serving to say they enjoy it. I can say, though, that I'm squarely in the middle and I rather enjoy my ASR games with players who are even beginnerer than I. They can be fun even if I'm poorly rested or stressed out, I can experiment with different ideas without feeling any pressure to be perfect, and I really like it when I get the sense they're learning something from the review.
Just notice the histogram is the