My OCD may be affecting my judgment here, but the colour blue sucks ass. Maybe it's just me, but the colour in its self seems washed out, bland and depressing. Aesthetics are all important, and it's not that the SmackDown logo sucks or the presentation (except the damn crowd) is bad, it's just in dire need of something fresh to look at.
The brand extension worked until about 2008, when WWE began to throw more of the bigger stars onto Raw. This could be both a good and bad thing I suppose, depending who and what it is you want to see on Friday night.
In regards to the time or day in which it is on, I am fully backing the move to Tuesday, if it were to go ahead. As all the WWE Network stuff is pre-taped and whatnot, SmackDown may become victim to the same treatment the network stuff gets, which is fans seeing it as a "secondary, less important show". And it's true, it has become that, but it doesn't mean it should be.
All in all, a new logo is essential if you were to really go for the facelift approach. Something a little different to before, as Raw as seen many new and revitalised logos in the past. A new shade of blue? Okay, I'm going too far now perhaps, but I do think that the same recycled colour scheme and logo is what makes SmackDown seem a little less important. A new colour scheme in the arena too please. I don't know what it is, but it always seems dull and gloomy in a SmackDown arena.
I know I'm asking for a lot, and it will cost money if you were to go ahead with all these changes, but I do think WWE would benefit from it, in the short run that is. Of course, the wrestling is the main attraction, but all these things together could really make SmackDown look good again.