1) wbond.net/sublime_packages/terminal is possibly the best you can get right now. It has 'open terminal here' functionality as I read.
2) Built-in sidebar kinda does what you want I think? Just drag a folder into sublime and it'll go in the sidebar.
3) github.com/SublimeText/CTags can help out. If CTags can index ruby files (I don't use Ruby so I don't know but I presume it can) then that might be your best bet. But if not, SCI will help. I found SCI a bit too intrusive and a bit slow to index files, etc. but maybe it's much better these days. I haven't used it for a few months.
Do have a look at wbond.net/sublime_packages/community to see if there's anything that might help you though...