Due to the trendy and inherently unstylish extremes in tie width, that is why the 3 inch middle ground is the best. A 3 inch tie is actually quite conservative and classic, a tie width common for decades until the 1970s ruined more than just rock n roll. The 3 inch tie is the neutral territory that will grow in popularity and commonality, especially as the 2 inch width becomes more widespread.
The three inch ties are more common with each passing day. My favorite locations to buy the "slimmer" ties are:
J. Crew - ties sold are exactly 3 inches in width (for the most part). They are very classically styled with great color combinations. The Italian silk knit tie the width shrinks to 2 1/2 inches, so wear it caustiously.
Pink - Thomas Pink has a nice selection of slim ties all for $100 a piece. The colors are typically either pinks or purples but they are nice.
Brooks Brothers - the conservative retailer has moved 3 inch ties into the regular rotation, albeit under the "slim" tie section. These are beautiful ties, including a lot of rep stripes and even some madder patterns (like the one pictured above). They also have a nice glen check that looks very sharp.
Ben Sherman - has a line of ties around the 3 inch width. They come in aggressive colors and patterns and sold widely at Macys. Some are more conservative than others, but it always good to have a few daring ties in the collection to spice up the white shirt and gray suit look.
Calvin Klein - a small but nice selection of skinny ties. They are simple designs but usually have a little flair to keep them visually engaging.
Burberry - also makes some very conservative looking slim ties. I think they may be a little over priced for the quality, personally opting for bespoke first, but they are very nice. Especially the classic Burberry check.
If you want a timeless style go with the 3 inch width. It will always be essential to a classic look and will never look as trendy as super skinny ties or the wide ties en vogue with the anchors at ESPN.