Yeah, it sounds like you're really off to a great start! There's nothing egregious, but it seems like a lot of areas could be trimmed a bit. $200/mo for groceries for a single guy seems a bit high, and the $130 gas bill as well (is that an average, or just the most recent?). Call up your internet provider, tell them you'd like to cancel, and they'll most likely offer you a special deal.
I think SwordGuy is right on how to treat the rental income--consider it a self-contained business. Your rent is the income, the maintenance, mortgage, insurance, etc are the expenses. Keep that compartmentalized, and any excess you take as income into your normal budget. Your net income in that 'business' is right around $0 ($1450 - 997 - 300 - 50 -100). That's fine, though--if you consider it that way, you're basically getting free housing!
A traditional IRA is probably preferable to the 401k, since you can make sure to invest in low-cost index funds rather than whatever your employer offers. And I'd go pre-tax (401k/IRA) rather than post-tax/Roth, too.
I wouldn't worry *too* much about your official savings rate. There's no hard-and-fast rule about what counts and what does not.
