I breastfed until DS stopped by himself which happened at about 4 years. It was a bit awkward at the end and felt a bit like a dirty little secret :( but I'm glad that I did it.
However in no way do I think this is right for everyone! I just wanted to provide a perspective saying that it is hard to imagine at 13 weeks just what it is like when they are older, because it's so totally different. At 13 weeks it is still very all-consuming and they are very reliant on you, by a year or so it's really not like that at all.
In my experience yes DS was clingy but I don't think it was because of BF - it's just a stage that they go through, some of my friends BF and had super-confident babies/toddlers and some bottlefed and had clingy ones, I didn't really see a massive correlation, unless you count that a parent who parents in quite a detached style tend not to breastfeed and also tend not to have clingy babies, but it didn't necessarily mean they were more adventurous either, but they tended to sit there and play without much input.
Evenings, work, etc, you can work around, you either just BF when you are there and they manage when you're not (they really do, it's quite bizarre) or you work into your routine not to BF at those times anyway.
Teeth are not an issue, not sure why, must just be the way it works, but you can't feel them at all unless they decide to bite and they can do that just as well with gums!
I reckon it's easier to stop before 18 months or after 3, so if you don't want to let them self-wean it's best to stop before 18 months or so if you want an easy ride - usually you can just substitute with something else and they are totally accepting. Obviously it's possible to stop at any age but I think you risk them being attached to it and it being an actual drawn out endeavour rather than just a simple thing.