The ‘secret’ to this salad is lightly roasting the vegetables; they are cooked just long enough to increase their natural sweetness yet not long enough to soften to mush. The veg is still firm (especially when chilled) but has a near-noodle quality when served.
This salad is fairly acidic (it uses balsamic and lemon) and you may wish to lower the amount of acid that you use; but I wouldn’t! Vinegar and beets are a natural combination (i.e. pickled beets) and this salad exploits their relationship. The addition of lemon makes it light and spring-like yet the amount of root vegetables also makes this a salad you could eat as a meal.