Hey Mookie welcome to AVS, I am also new to the forum as well but have been referencing to it for awhile now. I would say in my opinion that all leds have some problems with clouding not just bigger panels.
Some are worse then others the sharps do have it pretty bad and same as the vizios to, but I would never get a vizio there just terrible. I have been having some some problems with clouding myself on leds. I can't stand clouding, it's awful when watching movies or gaming at night.
I would recommend sony they're tv's are pretty solid for gaming but do have flaws just like any other tv like eclipsegt mentioned. It depends on what your using it most for. You mentioned you own an Xbox 360 but you watch sports. Remember input lag is always there on a high end tv it sucks but really only matters if you game competitively.
If you are a casual core gamer who enjoys cinematics and a videophile as well then by all means go high end and big, and don't worry about input lag. It sounds to me like you might watch sports and movies more so a decent refresh rate might matter to you (it also helps with gaming to).
I really don't care what people say but don't go plasma no matter what. I tried the hype and it didn't please. Like I said I've been in a tv fiasco myself recently, I just made a new tv purchase and been swaping out like crazy, not being satisfied with anything.
This goes into the whole plasma thing so please bare with me haha. Well the first tv I bought was an LG 47lm6700 it got very good reviews and was great on input lag and I'm a gamer so cough cough. Not to mention I was going for 2012 models since all of them were going on sale for new items to be stocked which in the long run I realized isn't a good idea.
Anyway the LG had hotspots (clouding) right out of the box really bad to, best buy didn't even have more in stock hence why going for last year's models isn't a good idea. So I swaped it for the 2013 panosonic 55st60 don't believe the hype I'm telling you, not even from cnet. I mean plasma is great for off viewing angles and color does pop. But everyone always fails to mention image retention even with high end models that have scrolling bars and pixel orbiters still get it.
Now mind you this was the second plasma I ever owned I used to have the HTC 50 blah blab whatever flagship model haha..when 3d was just coming around. That tv was the only one with no ghosting, BUT both plasmas I ever owned both being panosonic the best of plasma! Haha got image retention. In my opinion it's more annoying then clouding.
So back on track the st60 had ir the third day I used it, even just watching tv you'll get it and with sports the little espn logos and the score boards will stick I got the amc HD logo to stick on mine so take my advice everyone and just let plasma rest haha, I hope oled doesn't get ir on the count that they're going to be like the new plasma displays then again not really since they're organic light emitting diodes.
So from there I got the sony kdl-46hx750 I wanted a sony from the start but when I was there the sony was pricey for what I wanted, just a little tv for gaming note why I go 46" if your going to be gaming alot, smaller sizes are much better less input lag and better PQ.
Now Sony's are great but that's where I am now the hx750 turned out to be defected and I'm going through some problems with it, best buy gave me a wall unit of the sony since limited stock (note why I said don't go for last year's model).geek squad told me my problems were too specific, what? Also at that time I wasn't aware when you get a shelf unit your limited warranty gets voided (so never ever get a shelf unit), don't let them talk you into it like how they did with me.
So now here I'm waiting for someone else to come and hopefully give me an RA (replacement authorization). Sorry mookie just some words for thought.
Anyway sony is still amazing offering full 1080p 3d and an awesome refresh rate with the x-realality engine and with newer models the pro engine. In my opinion sony takes the cake with a better picture then samsung. So since you wanted to go big here are some big screen recommendations from Sony's new R and W series (which I'm hoping to get an RA with the kdl-47w802a), I recommend that you stay in the 55"-60" range since PQ will look more crisp but I'll start with biggest to smallest so here they are.
Kdl-70r520a: which is $2,398.00 it's 120hz smart but no 3d on the bright side it's pretty cheap for a 70" display.
kdl-60r550a this model is not priced on the best buy website but I found it on Amazon for $898.00 and $1,375.00 on eastcosttvs.com also pretty Damn cheap for a 60" no 240hz refresh rate but it does carry full 1080p HD 3d and four pairs of 3d glasses to come with it, also a nifty little feature on this bad boy is the capability to have directv with out a receiver it's built right in. I'm actually jealous of that haha.
And lastly it's a bit smaller but it's the one I would recommend the most, and that would be the Kdl-55w900a which is $2,299.98 now it is a 55" but I think that would look the most crisp in your room since you won't be that close to it. This tv comes packed with everything 1080p full 3d with four pairs of 3d glasses to accommodate it, smart features and a 240hz refresh rate running with the x-realality pro engine. Not to mention all of these models have local-dimming to reduce clouding.
So mookie sorry for the long post but I hope there was some good advice for you to follow. It's been a pleasure hope to hear from you.