I love love love blazers....although not the biggest fan of double-breasted options because most styles are too tight around my mid-section. To keep them looking slick, opt for skinny or fitted bottoms!
If you're taking the plunge but also want to get some regular use out of it, I'd recommend a navy pinstripe (like pictured above) or a "save" version here! You can always go for a touch of subdued color with this teal green version.
If you're not sure whether this is you, my recommendation is to stick with a pop of color and a slightly shorter length to get max use - this red blazer is the answer!!