[G6Tanuki]

These sorts of things are always fun to experiment with; lots of turns on the primary passing DC will increase the likelihood of core saturation [amps x turns] - if you're happy to sacrifice low-frequency response then use the fewest possible turns on the primary to minimise the core-magnetisation-effect.

[my experience is of AM transmitters, where we deliberately engineered a cutoff of audio frequencies below 300Hz because they contributed nothing to communications-efficiency; as a result the modulator-transformers looked rather lightweight compared with the iron seemingly popular these days with the audiophile types].