Just try to remember one thing... playing over an SMF does NOT mean necessarily playing over a commercial SMF. You don't HAVE to sound just like the original (and probably even the original artist doesn't perform the tune EXACTLY like the single)...
One of the best things that SMFs can do is to make your styles even more realistic. The nature of arrangers is that repetition thing... Same bassline for each variation, same fills for each transition, same horn licks in the second chorus as the first. But if you make your OWN SMFs from the arranger's output (so essentially, you are getting what you WOULD play if you were still in arranger mode), but then go the extra mile, and edit the SMF to help get rid of the repetition, and give it a bassline that sometimes moves in the direction of the NEXT chord change (something no arranger can do - anticipate a change), fills that are non-repetitive, etc., etc., you gain a backing that is NOT just a copy of the record, it is still your own creation.
Add to that the ability to play at least TWO parts at a time yourself on top of that backing (you've got two hands, don't you?
), so less need for automated parts at all, and you get something that the audience will definitely notice is more live, more PLAYED, than just sitting there inputting the same old changes over and over again while you bang out the melody with your RH.
Even though the backing is initially derived from the arranger output, you have knocked the sharp corners off the machine-like nature of it, and increased your degree of involvement in the final sound. Now take Mark/Jump abilities into consideration, and you have back a large degree of the arranger strength of re-ordering the sections.
And one last thing. Make the registration include the Link to the SMF, and also the original style it was derived from, and midway through the SMF, or at the end to extend or segue into another tune, you can simply stop the SMF and sync-start the arranger (some arrangers do this seamlessly, others simply need practice to do it manually, but it CAN be done), and carry on in the usual fashion.
Just don't get the fixed idea that SMF's ALWAYS have to be commercial files, and ALWAYS have to sound just like the record, and ALWAYS have to have too many parts.
They can be, if you let them, be just as distinctive and unique as your arranger playing, and if you use them to free your LH from the tyranny of inputting the same chords over and over again (I'm sorry, but I see few here with the ability to reharmonize a tune on the fly, from what I've heard -at least intentionally!
), you can at least DOUBLE the amount of music that YOU are playing (not the machine), and that is something the audience WILL notice, being different every night...