I'm having the same issues. Although I love TM, I wanted to move to something that was under active development and I had confidence in so I purchased ST2 after trying it for a week. Unfortunately I was working on a PHP project at the time and didn't realise the lack of support ST2 has for rails development out of the box (my bad).
The if+tab inserting a php block is a bug due to the scope of the php snippet which is covered in another post in this forum. I've spent several hours googling for help on ST2 + rails and have come to the conclusion that you have to either role your own or install a package from the community. Personally I dislike both of these options, as a freelance developer I tend to see my editor as a tool and dont want to spend time messing with it, and I'd prefer to have the company that developed the editor create the required plugins as I have more faith in the quality of their code etc.
I'm sure I'll get hammered for my opinions as there are a lot of people who love ST2, I'm one of those people who are happy to pay for good software and ST2 is definitely worth the money it cost me, but I'm contemplating moving to RubyMine for rails development maybe worth you having a look too.