First impression is vital for me, I look for the appearance of the site so the theme or style is the first thing I notice and take into account aswell as daily content. I like to see daily content coming in with a few active users so I am not talking to myself so to say. 😛
That would be tough as I have a few favourite forums and with new ones coming in as often as they do my favourite forum might change over time but I have always liked FP for the advertising help and advice aswell as the general community feel. 🙂
I haven't got anything in particular that I would change about FP as it is a wonderful forum already but I wouldn't mind seeing the quality improved as far as posting goes, if that counts as a change in your books. 😛
I don't mind either way as long as the posts are adding value and actually contributing to the topic but it's always good to see long and detailed posts where the member could well have put alot of effort into his or her's post so well done to them for taking the time and effort on their post, as for me it is quality over quantity. 🙂
I guess it would depend on what they put into that 'short post' and what is qualified as a 'short post' because there is a chance it could still add to the conversation as long as the post has been well thought out and not rushed like alot of short posts are.
I think it's okay to make shorter posts once in a while because nobody likes to see long-winded posts when they're not really needed and could just be described in a short and sweet way although alot of the time a more detailed post is the way to go, in my honest opinion.
So for example, if one was discussing an admin or webmaster related topic it should be fairly easy to reply to it with a few sentences or more, it's not exactly an uphill task really.