Sorry for the delay in responding:
2) It's still an open issue whether we will support both implicit and explicit phasing in R7RS-large. Personally, I think that since you are not allowed to give identifiers different definitions at different phases in R6RS (as you can in Racket), implicit phasing should suffice. The R7RS extensions to R6RS library syntax make more work for implementers, but less for users. In particular:
Allowing interspersed import and export declarations make it possible to keep them next to their referents;
Cond-expand support (which has no phasing problems because the features cannot be set from Scheme) is a more general kind of configuration;
Wrapping code in begin, include, or include-ci means that it's possible to add new clauses to the library language, since it is distinct from Scheme.
3) The WG looked at several different record proposals including SRFI 9, R6RS-syntax, and a couple of others. SRFI 9 narrowly won, beating an alternate proposal that would use R6RS syntax, SRFI-9 semantics, and a different name. Those who voted for SRFI 9 emphasized backward compatibility with existing code.
4a) I've added a note to the trunk of the draft (not yet published) warning about the unexpected behavior of binding parameters to self if the converter is not idempotent. I've only used converters as checkers myself, so it hasn't come up for me.
4b) Include is only allowed at program top level, macro top level, and REPL top level, so your code is not valid R7RS. I believe that disposes of this objection.
5) I've filed a ticket for this issue; like the other outstanding tickets at this stage, it will turn into a formal comment from the public review.
7) Two implementers have been negative about the effort, one of them definitely not in a Big N for any reasonable N. The Guile and Chicken maintainers have said that R7RS is a goal for them, though of course without a schedule or firm commitment, which would be premature at this stage. Another maintainer has said the same privately. But I think you overestimate how different R7RS actually is. Modulo the library syntax itself, I expect it will be trivial to provide all the R7RS libraries on any R6RS userland, for example. (I'm going to tackle it as a proof of concept if no one else does it first.)
If you have time, please take a look at the draft itself, or at least the list of changes from R5RS at the end, and comment further on email@example.com.