1.5.5 fixes the problem, so there is nothing to suggest. 
I assume that once the 1.5.x/2.0?-path has stabilized that your other enhancements and fixes will move into the final version, too.
Exposing the formatter interface to fiddle around with it might not be worth the work. The way 1.5.5 exposes the formatter interface is a good way to add individual changes. If it works (and 1.5.5 seems to work) and there is a way to fix the errors, so shall it be. There are other areas that could need work... and 1.5.5 still has the 5+ years old gcc.