The marathon is a difficult race to run and the training is difficult too, but that's part of the attaction of running a marathon; your goals require hard work and gritty determination to achieve. Many runners agree that the training is harder than the marathon itself, the training requires an investment of time and energy, you can not wing a marathon. Running a marathon and racing a marathon are not the same, if this is your first marathon then the goal is to run all of it without much concern for your time, but to race a marathon with a goal time in sight tests you physically and mentalyl against the clock and this is where the attaction of racing a marathon lies, how far can you push yourself to see what your limits are.
If you would like me to look over your training plans I will do, if you would like me to put together a 12 week training plan I will also do this, I am assuming though that you have already started your 16 week plan. I can help you with pace and the Wednesday evening sessions will help you with speed endurance and strength. I would also advise some strength training if you can fit it in, yoga and Pilates are also very complimentary to marathon training as well as fortnightly sports massages. Marathon training does tend to overtake your life for 16 weeks.
There are some significant races that I would advise you to do, Bramley 20 on the 11th Feb, Wimborne 20 on the 4th March. Cranleigh 21 on the 25th March is also a popular race to do as it is usually 3 weeks before London Marathon, this year is is 4 weeks before, so it is your decision on whether you run this one or not. Having races booked helps you prepare your nerves when running in big races, early starts, what to eat, how to deal with tummy issues all helps you to develop your own race prep routine. All of these things are so important though as it helps prepare you mentally and physical when you go to a race in a big event as it enables you to gain experience which can be built upon to help you succeed on the big day, things like what to wear, what is the best thing for you to eat the day before, what kind of breakfast is transportable for you and how many times you need to go to the loo.