TKTS prices are 50% of the box office price, plus a service charge ($3.50 I think). So orchestra tickets for a musical are going to generally be $53.50). I have never tried to see if there are other seats available, I just take whatever they give me, but it wouldn't hurt to ask if there were any balcony seats available for less money. IMHO it's always better to take a discount offer directly to the box office. You may pay a few dollars more, but you'll get to chose your seat and save hours of standing on line in Duffy Square. Another option is the TKTS booth near South Street Seaport. Lastly, I live in NY and never show up at TKTS before 7:45 and frequently get a great single for the show of my choice. I've heard that some shows release tickets close to showtime but i don't know that for sure.
'Our whole family shouts. It comes from us livin' so close to the railroad tracks'