Pull Back the Covers - 3 Steps to Optimize Your Set
First off, this isn't an article waging war against cover songs or cover bands because they definitely have a place in music and live performance. This is a theory (Agree or Disagree) to help original artists that have a big enough catalog of original songs to fill a whole show. Instead, you play majority covers (because you think you have to) and wonder why no one buys your music. Basically, just because you know all of the Tom Petty and Lynyrd Skynyrd “Hits” doesn't mean that you have to play them.

I have been working on a theory that could best optimize your knowledge of covers with out bastardizing your originals, by being more strategic with your cover songs. I think in a given 60 minute set an artist should play no more than 3 cover songs. Instead of playing Free bird every time someone catcalls for it. All these points are fairly self explanatory but are sometimes ignored.
There are three key points to this theory...
The 2-1-1 Placement – This is a pretty simple point (as a viewer). I like it when a Musician places 2 originals in front of a cover and follows with another original. If you are playing a 60-minute set (following this logic), you should play 11 Originals and 3 Cover Songs.
You don't want to get too deep into your set without playing a familiar tune, but you also don't want to play one right off the rip. If you play a cover song too soon, the audience assumes that you only play originals. But, if you don't play any covers, you could lose their attention.
The Blending Theory – Each original that sandwiches the cover should also complement the cover to make it blend naturally with the flow of the show; it should match your style. You don't want to go from an upbeat bluesy tune to a moderate southern rock tune. It'll throw off the flow of your show.
An Original Theory – When you are selecting cover songs, look at the ones you have the most unique twist or interpretation (to a new instrument) to. This way, it takes a cover song and makes it feel like an original.
Now obviously, this is only my opinion and you should ultimately be flexible and read the room. If you are losing the crowd, it's probably time to break out a “Standard”, but you can still utilize these 3 points in the selection of that song. The whole principle of this theory is to have your originals be the main course and to us cover songs as a good wine pairing.