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Therefore, it might be best to add additional gain stages in order to retain a modest winding ratio. Please understand that extra gain stages and an inter-stage transformer mean that a global feedback loop is ill-advised, but as the cathode follower configuration already provide both a low output impedance and low distortion, global feedback is probably not needed anyway.
Conceptually, the inter-stage transformer is king. In practice, it has been deposed, replaced by circuitry and coupling capacitors. The main problem with all high-quality audio transformers is that they are both expensive and hard to find. Another is that they often pick up noise from stray magnetic fields. But most damning, at least in the eyes of modern engineering practice, is their incompatibility with global feedback because of their limited bandwidth and audio-band phase shifts.
The reference points in the accordion amplifier depend on the output stage's function, either cathode follower or amplifier. Thus, designing a transformerless driver circuit requires a relativistic approach (similar to that used in designing an OTL amplifier), an approach with which few tube circuit designers are comfortable, alas.
(Many designers worship Ground, seeing in it the one and only reference point. They ascribe magical powers to Ground, claiming that Ground can never become noisy or RF polluted, and that Ground, like a black hole gobbling solar systems, can sink infinite current and voltage. When the reference point is moved to some different part of a circuit, these designers grow nervous, their knees weaken and they perspire. Not readily finding a Ground in the circlotron's output stage, they abandon this circuit for the more conventional and safe alternatives.)
If configured as cathode followers, then the reference points are ground for the top tube and the bottom tube's plate for the bottom tube. If configured as grounded-cathode amplifiers, then the reference points are ground for the bottom tube and the top tube's cathode for the top tube.
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