The khaki suit is a great option for the spring or summer, or in just a hotter more tropical climate. Definitely a cooler choice than wool!
I’m not as big a fan of it as some other guys, but if you live in a hotter area, it could definitely be a better choice than a grey, navy or black. I do like a nice pair of khaki pants though, especially in the summer. A lot of people will state the old Memorial Day to Labor Day rule of wearing khaki but I think it’s a little old-fashioned. I’ve seen it all months of the year. It might look a little out of place in January in Chicago though!
I think that one’s complexion has a little bit to do with how well a color matches. A light tan color can tend to “overpale” some lighter complexion guys. A darker British khaki might be a better option.
Some more conservative work places will be OK with wearing these occasionally, especially on summer Fridays. Personally, I think they look a little casual for a big stuffy law firm, but places like LA or Miami might be cool with it.
A nice blue shirt can really look nice with these. Some guys like a white shirt but I feel like that is too much “lightness” for me in a lot of cases. If you can pull it off, though, go for it. Other people also suggest pink shirts, which is kind of an interesting look. I like kind of a lavender shaded shirt.
As far as the tie, I think yellow looks good with a blue or lavender. I’ve seen guys with black ties, which personally I don’t really agree with, but hey it could be popular.