Well, seeing as your cheapest player is 70k your options are quite limited.
I reckon I'd go for:
8 High Elf Linemen (560k)
1 High Elf Blitzer (100k)
2 War Dancers (240k)
2 Rerolls (100k)
I've picked High Elf linemen over the Wood Elves because AV8 will help them survive a little longer in the scrum. You could mix & match line elves though, to get a little more speed. Trees are a waste of time (IMHO) - stick to the elves and play a fast & loose game. The War Dancers are there to take out the enemy ball carrier and score - the rest are just there to make sure the war dancers live long enough to do the job

You might also consider swapping out the High Elf Blitzer for a Catcher instead, to get a little more speed, but that could cost you in the stand up fights of the first few games.