Are you placing your lips right on the mic?
A better mic may help but at some point the rejection off the back will be irrelevant because sound will reflect of your face and teeth into the front of the mic.
The first thing I would consider is whether the audio tech is properly ringing the system for feedback. This involves turning the system up and then running through the system EQs to find and notch out the problem frequencies. Ringing the system can significantly increase gain before feedback and also improve the sound.
If you do get hyper- or super-cardioid, keep in mind the optimal position for your monitor moves from directly behind the mic to the sides.
View attachment 4724700
In my experience, you have to stay right on top of a hyper- or super-cardioid mic. A problem with this is the more directional a mic is, typically the stronger the proximity effect. Proximity effect means the low end becomes stronger as the mic gets closer to the sound source. The audio tech will need to use a high pass filter and fairly aggressive EQ down low to make your voice sound natural. If this is not done the sound will be very bass heavy (in a bad way).
This graphic show the proximity effect for a (hypercardioid) Beyerdynamic M88TG:
View attachment 4724706
In my experience, you have to stay right on top of a hyper- or super-cardioid mic. A problem with this is the more directional a mic is, typically the stronger the proximity effect. Proximity effect means the low end becomes stronger as the mic gets closer to the sound source. The audio tech will need to use a high pass filter and fairly aggressive EQ down low to make your voice sound natural. If this is not done the sound will be very bass heavy (in a bad way).
This graphic show the proximity effect for a (hypercardioid) Beyerdynamic M88TG:
View attachment 4724706
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