As an alternative to the hill session:
8 x 400 as:
1st 400 steady, 2nd 400 slightly faster (eg threshold pace), 3rd 400 slightly faster (eg 10k pace), 4th 400 jog recovery... and repeat. Continuous, no static recovery - just the 400m jogs.
Then up to 3 x 1k with 75s recovery.
Marathoners extra 20 mins at MP as per Alan's session.