This is indeed a complex question that really only you can answer. Along with what you have mentioned as criteria what other things are important to you? Is color accuracy more important than brightness? Just how much ambient light will there be? What is the source? What is the style of the room that the set will be used in? How do you want to mount it? Do you need it to have speakers or will you be using a separate sound system?
How many HDMI inputs will you need? Will you be using it with a PC? Do you require 1:1 pixel mapping?

I have a Sony Wega III in the living room that I have had for more than three years. It is a RP LCD and I have never had to change the bulb. I’m guessing that it is approaching 7000 hours of use. The screen material is such that it works very well in an area were reflections off of the screen are an issue as the screen has almost a matte finish.

I have a 42” Maxent plasma in the bedroom that is going on 1 year old. I paid less than $1000.00 for it. It is certainly not one of the best sets out there but it has served me well and was a bargain in my opinion. The plasma is MUCH brighter then the RP LCD but is prone to ghost images and has a very shiny screen that is not well suited for areas with a lot of reflected light. Plasmas are notorious for delivering a very bright, over saturated image. The light output will diminish over time with a plasma and can not be regained. If you like a bright picture and use the set with the contrast set high this will speed up the process. I very very rarely buy warrantees as I am of the belief that they are a waste of money but I did buy it for this. At $99.00 I felt it was worth it. I have heard good things about Mack warrantees but have never bought one personally.

I also have a JVC RS1 in a home theater. This is a FP that projects the image onto a 126” 16:9 screen. This is in a totally light controlled environment. It is by far the most pleasing and color accurate system that I own. While this is true I don’t think I would chose this as my choice if it were going to be the sole device that I would use for viewing.

I won’t even go DLP I am very susceptible to DLP rainbow effect.

I have somewhere a chart that examines screen resolution vs. eye acuity vs. distance to screen. I can’t find it at the moment but depending on what you intend to do you might find that you can’t tell the difference between 720p and 1080p in your environment.

Good Luck, there are a lot of choices out there the good thing is that there are few really bad ones.