Is it necessary to practice all professions like Dragon Seven?

You don't need to practice in every profession.

Let's start with men. If all men jump to the same job, Nanbo has the least blood, but his magic attack is the highest, so Nanbo is most suitable for male public relations (he is extremely good at fire and ice, and then inherits divination electricity), so the attack is more comprehensive.

Among the other men (except in spring), Zhao in Sao dialect has the highest physical attack, followed by Zuli. However, the extreme skill (non-professional) worthy of his role is a group, and he is the only one.

Han belongs to the development of physical and magical attacks, but neither is top-notch. He is the fastest. Han's own killer is the only one who has a high-skill group gun, but the damage will be scattered when this high-skill group gun hits many people, so the effect of clearing soldiers is average, so it can be replaced by the shooting range of Big Sister. The disadvantage is that the shooting range is difficult to judge.