For a room where the there will be decent amount of light, LCD may work better. Both types if TVs have +/- and you can find tons of info on that.
Is 65 inch too big? Of course not. As long as you sit at least about 8 feet away and it does not dwarf the room. Usually, you want as big a TV as you can stand or you will regret getting one that is smaller.
Also, it sounds that you prefer an over-bright TV so, in that case, go with LCD with LED backlight. They can be driven very bright and maintain sharpness.
The current Samsung 8 series is pretty good but you should shop around. Sharp, Sony, etc make some very good LCD/LED TVs