HC o would be much better than cape but I
So you do know that levelling GBs from PME to FE is extremely cheap, don't you?
(Still writing without having had a closer look at your math. I'm simply assuming that it's good, and that I won't disagree with the premises.)
If we're bringing "Arc-math" into it, then a lot will change.
However, some facts will remain, the most relevant one being this: The profits must still be calculated versus the expensive levels of the GBs, not the cheap ones. The only change will be to which levels are cheap, and which are expensive.
One thing that will change with "Arc-math" is that Arc owners can make a lot more FPs, in the same time, by patrolling the neighbourhood and FL with a calculator, than they can by scamming the Viking Settlement. With an active FL, half an hour spent doing calculations and taking notes (for future investments) will often result in hundreds of FPs, in the much more useful form of FP packs. The downside is that it's really boring, but so is endlessly repeating the first five viking quests.
These are, of course, not issues for new players and/or new cities. In the beginning, 25 FPs can be a lot, and make a real difference to the game play.
It remains, though, that you put much too much weight on FPs. While they are central to the game, extremely useful to have, and fun to win, if you focus too tightly on them, you'll end up tiring of the game. As long as you find FPs exciting, great, but you should lift your head enough to at least notice that there's more to the game. Maybe you'll gain an appreciation for Yggrasil's impressive attack bonus. One thing that hasn't been mentioned is time consumption. Once obtained, Yggdrasil provides benefits from the fist level, and only needs attention for a fraction of a second per day. With auto-collect, it needs no dedicated attention at all. There's something to be said for "slow, but steady". Or, if you will, "lazy, but steady". Then there's the goods and medals, of course.
But even then, the point still stands that most people don't put every single fp they earn into fp-producing GBs.
Very true. That would be an extremely boring and limited way of playing the game, wouldn't it? I also suspect that it wouldn't work out very well; though, for precisely that reason, it might be worthwhile, as an experiment.