You can now buy and sell champs (hover and E to sell)

Actual pool of champions working behind the scenes:

1 cost - 348

2 cost - 264

3 cost - 192

4 cost - 108

5 cost - 60 (including Lux)

Buying champions adds to bench. They don't combine yet.

The field doesn't work yet.

You can sell champions by highlighting them and pressing E.

You can drag the portraits of the benched units but it won't do anything except snap back to their slot.