Due to tradition and/or work schedules, most Christians meet together on Sundays. Because this is the day when Christians generally spend the most time together, it strikes me that this is also the day when the least preaching should take place. After all, Christians have no reason to proclaim the gospel to other Christians.
The remainder of the week is when Christians spend much more time with lost people. For example, I'm around a multitude of them for about twelve hours every day at work. Because Monday-Saturday is when we Christians interact most extensively with non-Christians, it is these days when much more preaching should be happening. It is the lost who are in desperate need of hearing the gospel of Jesus Christ.
Therefore, when thinking biblically, we must embrace the fact that preaching is a key part of evangelism. Therefore, it should be directed to those who do not know Christ. On the flip side, the gathering of the church family is for the purpose of mutual edification. It is a meeting of those who already know and cherish Christ. We help build one another up through the use of our spiritual gifts. While teaching should occur in this setting, there is no need for evangelism. There is also no need for the speech/lecture that occurs so frequently from pulpits.
Let's see less preaching on Sundays, and more on all other days.