The difference between the actual brokenness of the staff of healing and a glorified bug net makes them incomparable.
If you really think a staff that can heal (allegedly) all ailments is somehow on the same level as a big net that is "magic" because Shamiko put magic in its name, then you are definitely fooling yourself.>We dont know Shamiko's mana capacity
But we do. There have been literal chapters devoted to making her output even slightly better than absolute garbage. Momo, Lilith, Ogura... every expert agress that Shamiko's mana is terrible and her capacity is abyssmal. She will never be able to reliably use broken weapons for extended periods of time. She cant even keep up a dependant contract with Momo, which comparitively to something that breaks reality, should not be that hard.
The only reason Shamiko can do it at all is that the staff does 90% of the work, being a cheat weapon and all. And even in dreams, her literal domain, her mana drains like hell.>Shamiko should be able to counter all her weakneses
This is absurd on several levels, because her Kiki Kanri has obvious limits. It has a stat distribution trade-off which inherently limits it. HIgh speed? Shit control. High durability? Super heavy. If you then add having to focus on the staff on top of that, a low level brain demon like Shamiko cant multitask that well, that quickly.>Magical girls are also broken
Absolutely. But that's like comparing an ant to a ant-eater. I think Shamiko, whose power is supposed to revolve around dream diving, is just not made for combat at all. And then even mid-level Dark Clan like Lico have mental defenses that make Shamiko's ability plain useless.
Shamiko is a team player. She will never be a solo fighter or a solo problem solver. That's just goes against the theme of the manga anyway.