This whole situation bugs me...
Is this your home? Is it your dedicated viewing room or is it a rec room or is it a family room?
Why does the space matter? Because if it is in your basement and you go down there for quality TV viewing, then you have choices that you should make. All of which require some consideration IMO.
Yep, you can do a projector. Throw up a 92" diagonal screen, maybe even 100". It's going to be close to the floor, but you'll have room and it will work well and look great... if...
If you paint the room darker. Not beige - but dark brown. Dark grey or brown on the ceiling. I'm thinking you have ceiling tiles instead of a drywall ceiling, but either way, get $100 in paint and you can improve any projected image by a great deal. Room color is the #1 impact on image quality in an otherwise dark room.
If you swap out that light or come up with another lighting solution. The photos above are pretty good, but I set up a similar demonstration in my old family room setup using a projector that was not very bright at the time...
You can see how directional lighting, when added to a room, allows hundreds of watts of lighting to be added to the room with minimal impact on the screen.
The Sharp 70 display doesn't hold a candle to the 65" Panasonic plasma or the 64" Samsung plasmas.
What in the world are you talking about with image retention? Plasmas don't have much in the way of image retention as they suffer from uneven phosphor wear.
The on/off pixel response time far exceeds what LCD delivers (LED or traditional)
This means that they are better for... (get ready) ...watching sports and anything with fast motion in it.
The conerns - reflections - which it doesn't seem like you have to deal with.
Image burn-in. This occurs when you pause a TV show and then fall asleep - for several days. Seriously, I've had plasmas for 9 years and have had zero issues with this and I use my TV normally... my wife uses it excessively! Video games by my kids, AppleTV, media player, hours of God of War, hockey (Go Caps!), etc. You name it, we run it through the plasma, and at no point has burn-in ever presented itself as any type of issue. Image retention either. They are certainly POSSIBLE - but it takes active abuse, and your mention of sports and news is the opposite of abuse or anything which will hurt the image. I strongly suggest you do more research on this.
LCD - Does not look as good as plasma, and Sharp, while I think they are decent looking, don't look as good as Samsung or Sony does for LCD, and it costs a fair bit more to get Sony or Samsung above 65". I would stop with a Samsung 65" LED/LCD if I had to go the LCD route, but there is no chance I would in your situation and with what you are viewing.
What would I do in your situation? Hard to say. I certainly would not stick with the lighting I had in the room. More accurately, I would add some wire spot lights or something similar which were far more directional than a fluorescent tube in the room. Turn the tubes off, and go with the spots when I wanted light in the room when watching on my 92" setup. I would paint the walls dark and the ceiling dark... If none of that was going to happen, then I would get a 65" Panasonic ST series plasma and be completely psyched on that. I would not consider LCD.