I can't see how doing only steady mileage is the right thing. I would work in tempos and structured fartleks a couple of times a week. You can even do hilly fartleks and tempos. Find a hilly loop, work out which parts you'll go hard and which easy (ie harder up the hills, cruise down).
I would also be doing some strength and speed development, esp if track is your main focus. This can involve hills, but I wouldn't be doing any serious hills more than once a week. It puts a strain on your calves, Achilles etc. A solid tempo followed by some 30-40 sec hills is a good session.