I'm Asian, and I have a lot of thick hair that is mostly straight. It will wave unevenly if air dried. I've never been able to straighten it to salon blowout standards at home with a straight iron. (That is, I did the whole shebang - blow dried, straight ironed, appropriate product. It took forever when my hair was long, and I only got ho-hum results for my troubles.)
What has actually worked is getting a straight perm at an Asian salon. When my hair has been straight permed well, a simple blow dry will make it look salon perfect. However, I found the quality of the perms varied, and some were harder on my hair than others. But getting a straight perm is a commitment! The growout period isn't that bad if your hair is mostly straight (it's very noticeable if you have a strong natural curl), but you lose the flexibility to switch between wavy and straight styles.
I now have a much shorter cut. My stylist uses the straight iron, so I always look fantastic and sharp on the day of the cut, but I also like the polished but slight more relaxed look that I can create at home just by blow drying without needing my straight iron. I really appreciate having a much lower maintenance 'do!