I've got head off, but quick comment. I enjoyed some of your comments (sorry I didn't do a great job going through it in detail) and I just wanted to toss in a few comments:
1) Any deterministic set of physical laws leads to a 1 dimensional "logical"/information chain of events and this can be seen as a predetermined physical model that implies no "free will", which in a sense is ironically what the ideal of such a will would be - if free will was conditional and did not act in a predetermined fashion, then it wouldn't really be free
(On the other hand, this would not necessarily have to be reality, but at least any form of deterministic sets of rules we could derive would give this form and I don't know how "randomness" can exist so it would appear it must be the case, though its interesting to consider that a single selection of an "origin" out of an infinite space time would similarly require an infinite quantity of information, which would similarly imply that an infinite number of decisions could be distributed throughout time (though on a smaller infinite scale and less "densely" represented)).
2) Multiple dimensions arise from the influence of a single dimension of causation - there's a single clock that keeps time to everything in order that all motions can remain synchronized in a space and this singular source can be distributed or multiplexed into various ratios of motions in various dimensions. If there was more than a single such source then objects would not specifically move to one position and we'd have to add some higher level arbitration, which would then effectively become the same as that singular source. There could be multiple such sources for time but without a synchronization they would appear to not influence each other and would exist similar to separate existences and unrelated.
P.S. I think the idea of multiple parallel worlds/universes is true, though there's really only one relevant path and that's the unique one that someone happens to follow - the only significant component of this is really that the only control around is self control (in a predetermined sense - wherever you go, there you are, whatever that is, which is a big question mark in itself) and there's no way to drag or force something else along for the ride (just as altering one clock doesn't alter time on other clocks and time is an individual ability/property).