Part of the AL experience is being able to take your characters from table to table and season to season. By limiting PCs from Plane X to one-shot events, it is counterintuitive to the system and reduces player investment in the characters.
The "AL experience" isn't a single thing. Organized play changes constantly, because when it doesn't (even within a single program) it becomes boring. Change is always a stress point, but the lack of change is far worse. No one program can be exactly what all people desire. We all have too many different tastes. Changing things up helps the campaign speak to more people over that time.
For example, a tight storyline season is being used this time. This works really well with Ravenloft locking us in, because now we all have a mechanical reason to go through that season and not go off-track with other stories. That's one of the big goals of this season. As with all seasons, some will love that and others won't, but what we've seen over time is that change is good for the programs.
It's also a necessity in order to learn. You can't learn without trying out new ideas.
The reason that I'm a proponent for the third option is that it's the one that makes the most sense, given Cobra Command expecting WotC to do more with less this edition. Cobra Command would kick the kobold scat out of WotC for doing something that negatively affected the bottom line, nor do I expect Cobra Command to be willing to add to the AL staff for something that only appeals to a fraction of the user base. Thus, WotC is stuck with the unenviable task of trying to create products that appeal to as close to 100% of the user base as possible. Plus, they've already got the tools necessary to make it work: Story Origin and the Ravenloft rule.
As I said previously, it's no coincidence that Ravenloft was chosen as the first non-FR setting to see a published product. Its ability to intersect with other planes made it the perfect testing ground for AL rules regarding other planes without making the public aware that they're test subjects. We'll probably go back to FR for at least S5 and maybe S6, while WotC goes over the results of their experiment. My prediction is that by S7, we'll know the future of other planes being featured in published products and their place in the AL.
Your premise is, to be fully honest, off-base here. The way you perceive WotC and Hasbro to interact just isn't accurate. From all I've learned over the years, a simpler and far more accurate premise is this one: "We launched Ravenloft because we love the setting and we thought it would be awesome and excite people." That's how they choose seasons, in a nutshell. Their core belief is that great stories sell and they saw an opportunity to tell a great story with Ravenloft. It's one of Perkins' favorites, and it's great for designers to work on what excites them.
They do look at how a season intersects with their other efforts, but it isn't a primary decision around AL. I think they know that the AL team can deliver great adventures on any storyline. Bigger concerns are likely how well it works with other partners, who may have a harder time. For example, Spelljammer would need a lot of work to be integrated into their video game partnerships.
None of this really digs into a question about rules options. The decision of how to add rules options is largely at the AL level, but is primarily based on decades of experience dealing with these issues. Over all that time, some clear lessons emerge:
- Any option will be a huge issue for some players and they will want it badly/loudly
- The vast majority of players are unconcerned whether options are allowed, especially non-core book options
- Players have a better experience when the play options fit the setting
- Players do not like for the game to get bogged down with options
- Players do not like to see overly strong options and like having limits that prevent those popping up, even if it means the loss of some non-broken options
