Think Whirled Peas
Just because running is simple does not mean it is easy.
Relentless. Forward. Motion. <repeat>
Your toughness is made up of equal parts persistence and experience. You don't so much outrun your opponents as outlast and outsmart them, and the toughest opponent of all is the one inside your head." - Joe Henderson
Future running partner.
Welcome Q (you're far from a noob)! I'm not exactly a noop, though far from an expert. I'll probably add some thoughts to this a little later. CONGRATS on moving up to Marathon training!
Welcome Welcome! You and I have very similar goals and are very close in experience and ability. I am currently building a schedule myself and have my own thread here in this Forum which I use as kind of a log so its kind of long winded. A fewthings right off the bat: --Try to work up to about a 3hr long run. --Make your longest run at least 3 weeks before the race. --As you increase your long run and weekly mileage, use the 10% rule. You may be able to ramp up mileage faster but this is a good rule of thumb to help stay injury free. I think that given your half marathon PR, that you could run a respectable full marathon time without too much more work. Probably sub 4 hrs just lengthening your long run and your weekly mileage a little. Perhaps we can help each other stay on track.