Those girls are not weak, which makes sense, even if they arent the strongest, they are in a more advanced district of the city.
But they are lacking in some parts, first is true finishing power, their abilities have kick, but there is a noticeable gap between expectation and effect, maybe it is their non-traditional battle roles, or they just aren't leveled up enough.
Second is that despite having good initial coordination, when things go awry, that goes out the window pretty quick, there is clearly a lack of some factor to keep them with their "heads in the game" if things go sideways.
Kyouko has a good head, she clearly knows when she is lacking, but she may be too accommodating to Kaede's strong personality.
But they have potential, and they do combo their abilities well, which is trickier than you would think.