@leaverou has anyone submitted bug reports for the issues? I'd never heard of any of these problems before or seen any of them in any of the bug trackers, the only SVG issues I see open in firefox that's not related to browser themes and UI is a printing bug causing text offsets when opacity <1 and a linear gradient bug that was opened this last tuesday.
If nobody is reporting the things working incorrectly it's impossible to get them fixed.