One of my players took Dust Devil as a spell, but in practice, it did not perform as expected.
STR save: good, it is a rare save
1m duration, concentration: standard for a long-term spell
pushes enemies away: difficult to judge. On one hand, it can become useful and push enemies away. On the other, enemies can be pushed in an undesirable direction
5ft cube, affects all enemies within 5ft of it (so effectively affecting a 15ft square area): the same as Flaming Sphere
affects enemies at end of turn: very bad, enemies can easily avoid it, unless they are trapped/cannot move/cannot attack at range. Compare with Cloud of Daggers, for example, which damages at start of turn without a save
can be moved as bonus action, but has no effect on being moved: unlike Flaming Sphere, which can be slammed into an enemy
creates a vision-obscuring 10ft radius cloud of debris in specific terrain: good, but very situational
After we played around with it, Dust Devil just seemed lacklustre. Compared with Cloud of Daggers or Flaming Sphere, which have some way to guarantee damage, Dust Devil felt useless in a particular fight where it caused no damage.
What are good ways of using Dust Devil? Should it just be prepared for narrow dungeons with choke-point? Places with specific terrain for its vision-blocking effect? Or is there some specific team composition that makes it worthwhile to concentrate on?