At the BibleFresh preaching event one speaker shared about preaching to the 20’s-30’s generation. I think his name was Andy West (apologies Andy if I got your last name wrong). His talk will probably be available online in due course at this site.
He shared four styles of preaching that he observes among effective preaching to the younger adult generation. I’d like to offer the four styles he listed for your interest:
1. The Preacher Orator: “here is my argument!” – This is the expert speaker who will tend to fill venues with younger generation adults craving an authoritative word in an age where truth and depth are not common currency in everyday life. People flock to hear Tim Keller, for example. It is structured, linear, deep.
2. The Preacher Artist: “how would you feel…?” – This type of preacher paints pictures with words, engages through effective storytelling and is creatively imaginative.
3. The Preacher Conversationalist: “I’m like you…” – The preacher is an ordinary person who has honesty and integrity, connecting with the listeners.
4. The Preacher Facilitator: “Let’s go on a journey together.” – This preacher doesn’t so much dispense truth as help listeners to engage with the truth.
A few quick questions spring out of this:
A. Is this list complete, or are there other “styles” that are engaging effectively with the younger generation?
B. How much are we able to switch between styles as preachers in order to offer greater variety and appropriate engagement with our listeners? (This is a critical question on numerous levels of preaching and with all generations.)
C. Should we be proactively exploring team approaches to preaching ministry that would more deliberately match the preacher to the subject and the listeners for each specific Sunday?
Biblical Preaching 
In reading this it seems to me that the style should and would change based off, of the Text God lead the person too. All 4 could be seen in one sermon to it might be interesting to see the points of the sermon in different styles. Just my thoughts.
The effectiveness isn’t in a style, it is in the power of the Holy Spirit. I don’t want to be any of those styles if the Holy Spirit is not empowering His Words.
Let’s trust the Word, it will do the exact job God intended it to do on and in every heart that hears the Word.