Hello,
I think it would be very useful to have some form of notification when a post you've made is replyed to. Particularily, if the little orange envelope's number went up by one (it doesnt even have to be in a separate folder or whatever, as long as it says 'hey, you have a reply!'). On my old account, I ended up inadvertently ignoring people's responses
Anyway, if you get the time, I think a lot of people would find this really useful. Also, it might liven up the site if people can keep conversations going.
-Lunar