The article refers to sermons modeled in scripture. Where are sermons modeled---in the church meeting--- in scripture. There are examples of evangelistic sermons, in public in Jerusalem probably out on the street, in synagogues, in whatever setting Stephen was at when he was stoned, and in the Aereopagus in Athens. Where is the Biblical model for a sermon?
If we truly followed the 'regulative principle' then the church meeting would be very 'charismatic', and it would have multiple speakers and singers. Multiple members might offer a song, doctrine, tongue, revelation, and interpretation. More than one prophet would speak a revelatory message. Of course, this assumes the Spirit gifts and enables such things.
Where is a specific example of congregational singing 'in church.' If 'every one of you hath a psalm' in I Corinthians 14, that sounds like everyone having a solo. We could 'speak to yourselves in psalms, hymns, and spiritual songs' rather than congregationally.
The real overriding rule I see in scripture for what to do in church is 'Let all things be done unto edifying.' Another would be 'Let all things be done decently and in order.' That is the Lord's order, not man's. The Lord's order allows for multiple members of the body to take turns prophesying in an orderly manner. The traditional order is that the clergyman speaks from a pulpit and everyone else must be silent.
If one takes a 'regulative principle' approach to I Corinthians 14, he might forbid something like drama presentations, and might possibly forbid congregational singing and only allow solos. Another approach might allow it if it were done 'unto edifying.' Based on this we might allow something like a drama presentation or congregational singing. Honestly, I'm not a big fan of drama presentations as a common thing in actual church meetings, though I can't say I have grounds to oppose it. I am not against congregational singing, but I am in favor of solos as well, as long as it is done unto edifying.
Is I Corinthians 14 supposed to be an exhaustive list of all edifying activities? It doesn't include the Lord's Supper, referenced in chapter 11.