I really do not have a favourite preacher... I spend a lot of time in personal Bible study.
I can tel you a few things I will not accept from a preacher:
Asking for $$$
Not encouraging folks to read their Bibles regularly
Not giving ALL the Glory to God (and as such not publicly saying they are a servant/slave to the Gospel of Christ... as St Paul did in the Epistles he wrote).
If a preacher crosses over any of those lines... I usually will be very wary of what they say.
My favorite preacher is God, using his word to convict my heart.
What do I like in a human preacher?
Let's take the pastor at my church.
Well studied. He knows scripture and the base language of the new testament, Greek. He can explain why so called "improved" translations of the Greek are not improvements at all.
Friendly and approachable. He is not a celebrity, although my church has 1,100 and is growing.
Bible based. He is not a Joel Osteen, "I'm okay, you're okay" preacher. He follows the pattern of teaching used by Jesus in his earthly ministry, and by the Apostles via the Holy Spirit. I am troubled by the amount of time Osteen can speak without saying "Jesus." After all, this is ALL about the savior and our salvation through Him.
Easy to listen to. The sermon time flys by, as he is gifted by God to teach the word.
Well presented. He follows the guidance in the Bible regarding the dress for appropriate worship of God. No "T" shirts like you see in some of these youtube videos.
While shouting and pounding are annoying to me, I accept that some guest preachers come from a cultural background where this is expected and normal. I can take it in small doses.
I think that about covers it.
[Avatar photo from a Florida training accident. Everyone walked away.] 2 Tim 3:16-17