I am afraid that the dynamic range will be limited by the FM transmitter,
not so much by the FM receiver. For a normal voice link there is no reason
to have a dynamic range at the TX input (mike) in excess of 40dB so I fear
that no constructor will do any efford to increase the dynamic range at the
73, Rik ON7YD
If you can hear/see signals on your local setup the FM relayed signal will
be only a tiny bit worse due to additional distortion introduced by the
additional modulation and demodulation processes.
There is no additional dynamic range needed on the proviso that the receiver
is the same or comparable.