Dear Lawrence,
Thank you for your further comments about the larger spaces and some of the mathematical relations among the finite simple groups, Jordan exceptional algebra, etc. that act in them. I also note your comment about gravitation. Let me respond simply.
(1) Although the higher dimensional spaces are important mathematically, and they can be related to lower dimensional spaces by such entities as icosians, etc., I find that if I can define the lepton, quarks, and interaction bosons as states that span the 3-D and 4-D real spaces (or the unitary plane C2), then I may have a better grasp of their physical properties and behavior.
(2) In fact, if the b' quark shows up at the LHC, then leptons as 3-D geometrical entities and quarks as 4-D geometrical entities have ALL the right mathematical and physical properties. One only needs to go to higher dimensional spaces such a 10-D because the icosians telescope one up from 4-D to 8-D to 10-D space-time. There are important mathematical relations up in 10-D spacetime that seem to dictate why 4-D works so well for the physical properties of our universe, both as the dimension of the internal symmetry space in which the Standard Model acts and as the dimensions of space-time. I know some of them, but I suspect that a few more are yet to be uncovered.
(2) I also suspect that gravitation does not need to be quantized directly. There is a lot more to be done with the general relativistic Hamilton-Jacobi equation and a simple transformation than most people realize.
(3) I will read some of your posts.
Cheers