How do you make (and use properly) a Whitebeard team?

After this month's Sugo-Fest, I was lucky enough to pull an Edward Newgate. I was just curious to ask:
1) What are good units to put into a Whitebeard team?

2) How do you use a Whitebeard team properly?

3) Do you have to have 6* Whitebeard to make a good WB team, or can you still use Edward Newgate?

Thanks for all the help!

1)All these units in order of ATK: http://op-tc-eng-version.blogspot.com.au/p/characters.html

2)Whitebeard have this Special ''Reduce ALL enemies HP by 30%'' and this Captain Ability ''3x Boost ATK of Crew, when below 30% HP''

3)Sure a 6* Whitebeard have more ATK an HP than a 5* Whitebeard.

^^