1. The look of the forums isn't my department; I just maintain the server and make sure people can use it. Our founder handles the look/feel of the forums and she's a little busy with RL right now.
2. The PM system's cumbersome nature (that means unwieldy or clumsy, in case you weren't aware) isn't really a dealbreaker for me in terms of functionality.
3. YouTube is accessible via the "video" tag, if you bothered to look at the help file or looked at the Video icon in the editor. RTFM.
4. The "funky" characters are a byproduct of the database conversion and there's nothing I can do about unicode conversion issues at the database level, especially when going from one encoding to the next. Not to mention, each browser will render it differently, especially between IE and Firefox, since IE doesn't conform to any known standard.
5. The variation of smilies/emoticons are an even lower priority on my list than the PM system.
If you're willing to donate $400+ per year for Invision v4, I'm willing to go back to it. But the problem for me was cost and crap support when things broke under their system, which is why we left IPB in the first place.
And here's a YouTube video to prove my point: