I have played a fair bit in my younger days and more recently as well.
I found the training changed a lot depending on the time of year.
Off season... hit the weights and keep some sort of run in your legs.
Preseason was always the real gut buster stuff. 1km and 3km time trials and sprints mixed with agility (Basically intervals between sprints and jogs). Of course balls skills mixed in on different days as well.
Closer to the season was similar to the above but with ball skills after, fatigued ball skills was a real killer.
In season training was ball skills and in game structure.... oh and recovery from games!
I always tried doing weights in season as well but found I could never get decent progress during that time, best to try and just maintain I guess.
This website has some interesting info:
http://www.fitfooty.com/
We took out the premiership last year as well
was a great experience! Decided it was a good time to hang the boots up as well.
Now just focusing on the gym and weight training!