<p>Here are my thoughts on the subject:
</p><p>Haruhime is technically a mage (sorceress), and like all pure casters, she will always need permanent protection.
</p><p>Even if she were to learn concurrent chanting, she would never become a frontline fighter, and would still need to be surrounded on all sides in order to be safe.
</p><p>Higher level mages like Riveria can defend themselves in close-quarter combat, but only against weaker opponents.
</p><p>In Haruhime's case, there were no such opponents until very recently.
</p><p>Welf's armors may seem to be unreliable, but you have to keep one thing in mind: Bell's endurance.
</p><p>In his "last-know status updates", Bell's endurance has always reached SS-rank, which means that he had to endure considerable punishment in order to do so, and so did his armor.
</p><p>Since each iteration of the Pyonkichi series tends to last a few volumes, it would be more than adequate for a normal adventurer's needs, but Bell is anything but normal.
</p><p>With Liaris Freeze increasing his growth rate tenfold or so, it would be unreasonable to expect Welf's creation to be able to keep up with this frenetic pace.
</p><p>Whenever they fail, Bell is up against insurmountable odds, with him being armor-less making the situation seem even more dire, making it more of a plot device than anything.
</p><p>As for magic swords, they may not contribute to the growth of their users, but UMS are sure to be different, since they are fueled by the mind of those who wield them rather than having reserves of their own.
</p><p>While I may dislike Uchide no Kozuchi, fifteen minutes is more than enough to put an end to most minor fights, and its duration will most likely increase due to a combination of Mikuzumenohou and Haruhime's level 2 status.
</p><p>All things considered, the rest of Hestia Familia may be holding Bell back, but they are also pushing him forward in their own way, and would be quite overpowered in level-appropriate expeditions, if Bell ever left for greener pastures.
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