There are several things I dislike about your UI, but it's just my opinion, so take that as you will.
The first issue I see with your UI is how much space it takes. The bottom panel covers over 30% of your screen real estate, which for a small monitor can be a big issue. You could reduce the amount of space wasted on the bottom panel by going over your action bars. From what I can see, you have 2 Inscription Buttons, 2 trinket buttons (could macro them), 2 mana gem buttons, 4 mount buttons (could use a macro, or have your mounts in a faded out action bar. Hide the menu / bag bars and make your Ports fade out.
Hide grid when Solo.
You have unit frames a HUD, AND Grid. Why? I understand Grid for instances / raids (you can still hide it when Solo) but why do you need unit frames and HUD? You get the same info, just in a different shape. Pick one and stick with it.
Time stamps in your chatmod are not very useful, imo.
Do you really need a damage meter to show your 72.6 dps when solo? No? Then hide it.
SLDT isn't locked (and you could hide some of them, do you need to know how much memory your addons are using?).
Do you need to know your coordinates in the minimap? Zone text?
There's a bunch of stuff you could do to make your UI look better (to me, that is). In the end, it's all personal choice, so I can't say "OMG UR UI's LE TERRIBLE!" but you don't seem to have put a lot of effort into it and could probably do better. Read this.
Thanks alot for the adivce Saed, nice to see some one being useful instead of just "AHAHAHAHA" or "It sucks"
I have taken into consideration some of your things and have put together a cleaner UI, while I still have the SLDT stuff all out (I like to see what's going on ), and many buttons on my action bar, I think I have cut down ALOT on the real estate that I am using. I still have Grid up, just to show that it's there (when I'm actually playing I have it hidden, though), and have gotten completely rid of iceHUD.
I only kept out my "Player", "target" and "target of target" unit frames, and I'm thinking of getting rid of portraits to even further clean up the screen. Right now I am using xperl, but am thinking of going a different route, simply for screen saving purposes. I have also found a nifty addon called "Party's Over" that gets rid of party frames (Grid would replace those). Also probably going to reduce MSBT font size, looking too big for me right now.