i've flown both LH & TG in C in longhaul. i'd def take TG anyday. their flight times are often more convienent, flight attendents helpful, curteous, entertainment, food etc.
i also agree that the thai traditional dresses are a nice touch. much much much nicer than their "western" uniforms. what i don't understand if why they can't wear their tradtiional dresses the whole time. other asian carriers- SG, Malaysia, Indian (?), wear tradtiional dresses the whole time.