SMF sucks pretty bad for a forum of this size, and is not at all good enough. They make too many assumptions and don't give enough choices for certain things. Theymos fixed some things, this would be broken in any upgrade and would need to be done again.
No way to see all threads created by a user.
Can't watch a thread without posting in it, can't unwatch a thread without deleting your post (which doesn't always work). (fixed by theymos)
No way to add notes to a user that would be visible to mods, only admins.
Only admins can ban people (somewhat fixed by theymos).
No ban queue, we literally have a thread in the staff forum called banning where mods post to report bans.
No way for non-admin mods to see current ban status (I can actually see big red warning text in a user's profile when they are banned, which is
handy and saves a lot of time, there's even a button to click on to take you to the ban where you can see reason and duration, I am amazed they got that right).
No way to ban multiple people at the same time, and bans are so slow it's painful, I almost want to stab myself. I have stuff to do and limited time here, just do it already sdaasdjasdjkliuodas. (partially fixed by theymos, but those are only for permanent bans).
Speaking of which, when you go to ban someone, better hope he hasn't been banned before, it will give you an error. Then you get to click on ban list, and go through page by page looking for the previous ban so you can see the reason and duration. Search? What's that? Get bent. Then modify the ban group (typically the username, I add a number) so it will go through and do it again. Then wait (see above).
No way to see previous bans of a user without poring over the banlist, which has no search.
No way to see deleted posts without using the forum search, or poring over the post history.
Want to see who locked or moved a thread? Sure just go check the modlog. There's even a search bar!!! But wait, it only searches by the moderator who took the action. No way to search the other fields, such as thread, user involved, date, etc. I honestly feel like I'm being trolled when I see that. Have fun looking through page after page (20 results per page, and there's a lot of pages).
Honestly I could go on and on and on...and on and on.