I wouldn't say it is on its last legs. From the text you provided yours is a little low, but that could be from a dirty air filter, low idle, loss of vacuum, low compression, etc... As long as it is steady I wouldn't worry about it, but I'm not you. What's the long term fuel trim look like? If it's negative then you may have a point, but if it's positive or close to 0 then I wouldn't worry about it, but again, I'm not you.