First of all, great review!
However, it looks like the figure suffers from the same problems overall. I still plan on getting Bruty, but only the cheapest version, i.e. G2. Some of these colors don't work for me, yet I do like Onslaught's color scheme more than the SDCC version.
Hopefully these sell well enough in retail for Hasbro to give the combiners another go with better sizing, better tabs and improved engineering.
Bottom line though, I really do feel that a lot of the problems/complaints could be solved if Onslaught was Voyager size.