What do you mean you can't see who people are replying to on reddit? Replies are organized and indented quite nicely. As far as I can tell, 4chan just uses a cryptic number, and the replies can be anywhere in the thread.
I mean posts aren't numbered and the id of the post(s) that are being replied to aren't visible in the post itself.
4chan's "cryptic number" system is pretty much perfect. You click on the number and it expands inline to the comment itself. All the posts that replied to a given post are also added to the header of that post and clicking on those numbers inline-expands the comments. The best part is you can reply to several comments at once with just one comment - the thread isn't a tree, it's a directed acyclic graph. If three people give you roughly the same reply you can reply to all three posts at once. I find this a very good feature for discussions, where very often there are several micro-threads going on on a single sub-topic inside a thread, it allows to keep everything neatly organised and you can reference people to other posts easily just by number. It used to be more cubersome before the current built-in javascript extension, when posts didn't expand and you couldn't see replies to a post tacked as references on the post itself, but today it's really really good.
I urge you to try a more tame board, say /g/ (technology), and see for yourself how things work now. It's usually best around after 6-7 PM USA time (any coast), when the people who don't live to shitpost get home from work.
Edit: to be pedantically correct (the even better kind of correct), you can make a post that quotes a future post and with really good statistical modelling and some luck, you can arrange to post in the same thread with that exact number, forming a full cycle - a post that quotes a future post that quotes the first post. This was much easier early on. I think the highest achievement was one person who managed to pull it off across several different boards while roleplaying a time-traveler.
I wasn't aware of those features, that would significantly improve what I thought of it. However having to click to see replies seems less than ideal. Reddit and HN just organize them properly to begin with. It also gets rid of voting, which I believe to be the most important feature.
