I figured I would throw all of my thoughts together in one post, although they have pretty much been mentioned by somebody else in this topic.
1) Editing posts - I would love to be able to go back and make little corrections in case I misspell something or accidentally leave a muddy point. A time frame would work nicely to help preserve the integrity of the current system. I would also like to be able to completely delete a post in case I respond just a hair too late and have duplicate information of another post. Again, time frame would work.
2) Viewing topics - I'm spending a lot of time on these forums now on a spotty internet connection or on a 7-year-old iBook (300MHz CPU), so it can take quite some time to sift through the topics one post at a time. I really like the easy-to-follow threading of topics here on CNET. If nothing else, it helps to make sure that tangents, regardless of how wild, can be contained and viewed as such. However, I would like more than one post to load at a time. I think that some sort of option regarding how to view topics would be great. You could have options like flat, thread, and I believe I've seen options for hybrid modes elsewhere. Hybrid mode could start off by looking like a flat view, but have posts indented to show the threading.
3) More tools - Let me explain what I mean by this. When you make a post here, you are presented with topic and body text boxes. That's it. I think more editing tools should be available to the poster. For instance, click a button and you are now typing bold (if tags are used, one click could be the start tag and the next click the end tag)[common practice]. However, I think the options should be limited. Bold, italics, underlining, and urls are about all that I would allow.
4) Change location and/or coloring of new topic and reply buttons - I haven't had a problem with this, but I think that just about all of us have seen when somebody clicks the wrong button and accidentally makes a new topic. New coloring, or at least different button positions should alleviate the troubles.
5) Avatars and signatures - having forum avatars is always fun and helps you to identify people easier. I think it should be separate from profile pictures. people should have the option to turn off avatar viewing, in case they are having problems loading pages. Obviously, size needs to be limited here. As for signatures, it would be nice to have the forums automatically add in my "-Ryan" that I always tack on. I think it should be limited to text and only x number of characters. There should also be a checkbox in the editor to disable the default signature in case somebody wants to make a different signature for one particular post.
Okay, I think that is about everything I have to add (at least for now). Sorry for the length, but I hope that everything is explained well enough to provide the best input possible.