400 not that bad for a distance runner. 800 just shows you've got little to no leg speed and you probably haven't run very man of them. The 1500 tells me that you've got no leg speed but decent stamina at your high end speed.
The thing that really sticks out is your 5k time. I have similar 10k/HM times (32:03 and 71:59) but have run 15:06 for 5k. Were these times on the track or roads?
In my opinion, I think you should work on your basic speed a little bit. My favorite way of doing this is by doing what 4x150m accels. On a track, accelerate from ~VO2 to mile to 400m pace over each 50m segment and then jog 250m and repeat. I know improving your sprinting speed sounds a little silly when doing lost distance prep, but sometimes that is a key (and very often neglected) factor when you're loggin a lot of miles.