very disappointed with emirates airlines

Travelled to Europe and back in July: (1) tried to book front row seats as I have a DVT in leg and doctor's letter saying I need to keep leg straight and up. We arrived 4 hours early for each flight, as advised by emirates by phone, but was refused on each flight as my daughter is 17, yet every flight had under 18 passengers in that row. (2) flying via Dubai causes endless delays and long bus rides - the airport appears to be far too busy. (3) one piece of luggage arrived 2 days late. On the flight emirates required that we complete a form and promised delivery to our hotel. We were never advised that we had to report to Russian customs. Suggest emirates have a preprinted form with detailed instructions to give affected passengers on flights so others do not suffer as we did. Had to pay taxi fare to and from airport (2600 rubles), and emirates escaped these costs, plus payment to customs (7114 rubles with commissions), and had to waste 5 hours getting the luggage so forfeited a big portion of our prepaid tours - a whole afternoon of our limited 3 days in St Petersburg. I expect emirates to refund these costs, and aplogize. I sent a detailed written complaint on 26 July which was acknowledged but to dated have had no response from Emirates.