Other than one Lastolite knitted background that I use about once a year, I no longer use any fabric backgrounds. I really dislike them and I do tire of even the coolest ones so quickly.
If you're producing work for clients then you could use one background and it's fine, but if you're going to have a portfolio or image gallery to show potential clients, you don't want to be the guy that uses the same background all the time.
I use large rolls of seamless paper, in black, gray and white. I can use gels and project patterns all day long and never have the same background. I also use a faux stucco white wall and have a textured concrete wall outside my studio.
The other thing I do is to have 4 ft. x 8 ft. sheets of tile board or masonite that I paint and create abstracts or textured surfaces. When I'm tired of it I paint it again and after it's been used and used, I chop it up, toss it and get a few new panels. This gives me the greatest flexibility and lets me explore all my ideas for color, texture, color wash, etc.
When I do things like family and family location portraits (about once a year.... it's just not my thing) where I couldn't work outside or had to work in someone's home, I use the simplest knitted background I could find with the softest look and none of the color mottling that I hate so much.
Lastolite has a line of knitted backgrounds that are large enough to put behind a group and whether it's in focus or out of focus it's not distracting and doesn't introduce anything other than a very light bluish, sky-like wash behind them. It's 10 ft. x 24 ft. and I only have one. Denny Manufacturing also have a line of knitted, wrinkle free backgrounds in a wider variety of styles and color but they are also much more expensive.
It should also be noted that wrinkle free backgrounds don't pop out of the bag with no wrinkles. The concept is that once you stretch it tight and clamp it off to light stands, there are no visible wrinkles, whereas if you did that with a muslin background you'd still have creases and wrinkles. The knitted backgrounds are outstanding for working quickly and not worrying about how close you are or what aperture you shoot to get rid of wrinkles.