As I mentioned in the comments, I cannot bake at a resolution of 512, but here is just a quick overview in which way the Resolution Divisions affect the appearance of smoke as well as how much influence the Slow option in the Dissolve settings has. You have disabled it, have a very high resolution and a very short Dissolve time.
In the comparison below, all smoke domain and emitter settings are the same and all images are rendered on the same frame, the only changes made are the Resolution Divisions from 50 to 150 and the Slow option being enabled and disabled. Since you need a high resolution you might consider increasing the Time for dissolving and/or enabling the Slow option, because as you can see a higher resolution results in seemingly less and slower rising smoke, and of course dissolving quicker without the Slow option.
Just for info: Use Flow was enabled until frame #15, Time for dissolving was 20 frames (a little more than your example to give the smoke a chance to rise) and the images are rendered on frame #40.