I pretty much want to sound like a small combo...drums, bass, guitar, piano, sax, mostly in that order. I also use Pedal Steel, Fiddle, Harmonica, Organ, Trumpet and Strings some, but almost always in a small group concept.
Mostly basic, generic styles are used, several each of slow and fast 4/4, 3/4, 6/8, 2/4, shuffles, and Rumba, Beguine, Bossanova. I do a lot of early rock n roll and country, which were often played by small bands with 3 to 6 players. When I do Standards or more Big Band songs, I usually still try to stay true to the small group concept as much as possible.
I do use a few "song" styles, but not many, and very seldom pull up a midi file of something that is difficult to arrange because of timing changes or very unique things that I find hard to play. Generally I learn to play them eventually and then discontinue using the midi file.
I certainly don't object to using and playing along with midi files or even MP3s, I just like to play as much live as possible. That's why I got into music in the first place, to PLAY it. The vast majority of my listeners have heard me many times so I like to maintain the overall sound but keep things as fresh as possible.
I miss playing with other musicians and wish it would have been easier to make a living doing such, but there are certainly many advantages of doing it alone. I get to keep all the money, for one thing.

Back to the question...I could get by with a dozen styles and a half dozen sounds if necessary, but night after night, week after week, year after year, you have to expand and change things or you would bore yourself to death, and most likely your audiences as well. As many know, I play a lot of guitar-sound leads and fills, and there are countless different guitar sounds if you consider acoustic, electric, and all the myriad of amp simulations.
Ever notice how old people tend to ramble on?