If you're starting on a new server...
Or have only one account to begin with.

A > B > C
A > D > E

With the booster on "A", makes a lot of sense.





If you have five accounts...
And want to level three more teams, that you missed initially.

Adding two accounts, and going:
A Booster
B > C
D > E

That makes sense.

It all depends on what you want to do.