Two things I'd like to see...

[m3talc0re]

1) Custom BBCodes would be nice...

2) Post seperation would be nice, too. Like in vBulletin (I had to add it to ipb), have it like:

----------------------------------------------------------
*bar with bg*  Date
----------------------------------------------------------
Author Info   | ____post title__________________________
                  |                                                             
                  | User's post goes here, etc....                     
                  |

You know how it goes.

[codenaught]

Custom BBcodes may make it into the next feature update of SMF (After 1.1).

As for the second suggestion, that is fairly easy to do with a simple change to the display template in the theme.

[Anguz]

There's a mod by me for custom bbcodes. The look of posts you can modify in a custom theme made by yourself, look in the Graphics and Templates board for help if you need it.