Jobu, it isn't actually MORE efficient than SOKs because you need a few of the non-FP producing buildings in order to get the proper bonuses. The Palaces need to touch 4 unique buildings and the Towers need 2. So 2 Palace configuration I was talking about actually requires 80 spaces. (the road profile is similar to SOKs though ever so slightly better, so I'm ignoring it.)
Stephen Longshanks, There is a super simple 2 Palace configuration that fulfills all of that with 1 of each of the decoration buildings and 2 West/2East towers. Basically you put the Palaces on top of each other with them sharing a unique decoration on each side. The towers go on each side of the decorations. That configuration takes up 56 spaces and provides 12 FPs and 20 goods (plus various other coins/supplies/happiness) Similar FPs from SOKs would be 48 spaces but no goods.
You can see some of the configurations
here
The 8 East Tower configuration I talked about requires 3 decorations (2 unique) and one West Tower. Note you can pretty freely substitute West Towers and East Towers depending on what you get, or whether or not you want goods or FPs.
There is a pretty good 3 Palace configuration as well but I can't imagine getting the right pieces without spending diamonds.
Also note that there is a one palace configuration which is pretty dense for FPs as well. It is 1 Palace, 6 East Towers, and 1 of each of the other buildings. That is 11 FPs, 10 goods, a bunch of coins/happiness/supplies on 52 spaces. That seems very doable since you get 1 of each tower and 1 palace through the quests.
The towers tend to be silver rewards on the wheel, and I have seen the palace in both silver/gold positions. Ideally you would spin with SOK in the gold position and towers or set piece decorations in 2 of the other positions. I've seen that already once. Less than ideally you might spin with a Reno Kit or Palace in the gold slot and the good silver slots. My strategy is to spin when there is something great in the gold slot (because obviously you want that), or something good in the gold slot with at least two good silver slot possibilities. (One up kits can substitute in for good set piece positions for example). You're going to have tickets anyway, it isn't like you aren't going to spin at all.
Again, SOKs are better. They can be motivated to double the coin production and are a very dense method of producing FPs. Unfortunately it looks to me like Inno is getting very stingy about them, so being able to plan on the field of 90 SOKs that some experienced players have seems less likely. Can these sets work efficiently while you are waiting to get a field of SOKs? I think they probably can
in eras where working the supply building quest is already inefficient. Now it is certainly possible that I've missed something in the above analysis, especially since I'm not in one of those eras right now. I'm also assuming that you can't watch your wheel like a hawk to be sure to only use your spins on SOKs.
But that is my thinking at this point.