robots would really clash with the medievel style of the armatars. So I really think we should like. . . .yeah. Not do robots. Costom color for profile would be nice. But what do you mean by design?
Custom colours/backgrounds/banners/designs -- they've all been discussed before. Is it beneficial to the site right now? Not really! Does it add a ton of personality? Heck yeah! I guess developers of the website are more interested in figuring out how to maintain and fix the little buggies, while slowly coming out with new things for the future. I'm sure we'll see it then.
I'm not quite sure what you mean by "Last Log In" -- it sounds pointless, but prove me wrong!
robots. Cougars. guys with flames coming out of their heads. skulls. Yep, all really medieval...
A last log in would be kinda cool, but really only if you are competing with someone for that particular thing. Or you were wondering why someone hasn't replied to you..
ie: either they don't WANT to reply to you or they haven't been on the site.
I really like the last log in idea, I don't if i has been suggested before, but I like it. The other two ideas are a little iffy, I don't think they will happen anytime soon.
if there was a such problem like a slow server or something , then the last login date would be necessary. And since there was a such thing happening (once, dont know if its true or not) then why not.