I wonder if we can try to somehow expedite the process for the next game.
Well, I think that what you are touching upon is the sentiment that Sun Tzu Wu was trying to get at, although his efforts to persuade others were relatively unsuccessful by large, as teams went ahead and made very accurate test games, used spreadsheets, etc--not all teams, but enough teams did.
Certainly, nothing prevents a team from discarding some of these approaches, but you'd still want something to replace them. For example, rather than setting specific turnset lengths, you could simply pick players on your team that are good at doing "such and such a thing" and have them play for a short bit of time at the relevant points in the game. You would probably want very short turnsets with a lot of hand-offs.
Things can get tricky when you have players with different levels of expertise in 2 simulatenous things that are occuring--such as an ongoing war and something else going on, such as tech trading or Great Person management.
Another tangental thought is that a lot of great micromanagement can occur without having a script to follow, but you need someone who is a relative expert in that kind of micro to be able to do it by the seat of their pants.
Even then, by playing around with a test game, you can get more people involved and you can get more useful feedback to help in refining even the micro of the top players.
Not every player wants others poking their noses in and giving them feedback on how to play, but players that don't want that kind of feedback can be given turnsets where the micro does not really play as much of a factor.
I agree that it is tough to find a good balance.
I think that it helps to play using ways that involve teammates. For example, I have read a LOT of succession games and many of them are just plain boring or non-engaging. In fact, some of the shorter succession games are a lot harder to follow; even though you would think that "shorter/less messages = easier to follow," it is often not the case. The people who are doing the reading really have to be interested in the subject, and if that interest is not there, then the level of detail is irrelevant.
Also, just as much as some people can be turned off by a detailed discussion, others can be turned off by a lack of details, particularly when a player goes ahead and plays by making decisions without consulting others or where they ignore the feedback of others. I do not think that we suffered from the latter issue in this game, but it is all too easy to happen--and it can be very frustrating for someone to watch poor decisions being made that could have been easily improved upon with a bit better communication amongst team members. Often, you will see this behaviour occur when the Active Player feels that they have to "prove themselves" or "demonstrate their awesomeness," but in so doing they usually end up doing the reverse, because they forget that good communication and team-play are important aspects of a good succession game, far more than individual greatness.
Another possibility is to have "roles" for the various players. For example, there could be someone that looks after trading, another person that looks after war deployments, another person that looks after whipping timing, etc.
The trouble with this kind of approach arises from the fact that while discussions can be done in a group, playing is done individually. For example, the person who is good at tech trading is often that way because the look for trading opportunities on every turn and they understand the implications of various trades that are made. However, the strength of this player will be greatly handicapped when someone else plays as the Active Player without even looking at the F4 -> TECHS screen and just plays ahead for several turns. A lot of potential trade opportunities are lost this way with the player who has expertise in the relevant area being unable to offer feedback.
So, in a way, we all need to be overall experts or else we all need to contribute our expertise to the Active Player so that the Active Player can become a temporary expert in multiple areas.
Since it is really hard to become an instant expert, tools like test games, spreadsheets, etc, are often used to enable that player to play various aspects of a particular turnset as though they are an expert in many areas. It is up to that particular player whether they will learn from the experience or whether they will just choose to feel like they are playing a game that is "so well scripted that even a 7 year old could do it."
Add to these facts the concept that a lot of things cannot be scripted--yet these things are still important to keep in mind--such as an AI going into "hands full" mode--and it is easy to see that the Active Player already has a lot of issues and details to deal with, regardless of whether they have any spreadsheets or other aids to help them remember other aspects of the game that can be pre-planned.
I do not profess to have an answer, but I think that it is a worthwhile issue to discuss.
Ultimately, the players who agree to play should feel comfortable with whatever approach is chosen, and if they can relatively agree on an approach that they are all comfortable with using, then it will be a fun and enjoyable experience for everyone, whether that be microing to the nth degree, using a totally-hands off mode, or likely somewhere in the broad spectrum in between the two extremes.