I've taught double reeds and saxophone together (in the past) for many years. I've always had them play in unison.

I've had colleagues that taught high brass with horns playing the same letter name as the trumpets and it worked out fine.

The biggest thing with the sax kiddos is you have to speak in tuner note/versus sax note until they are used to the concept (really, if they can understand Concert F and Bb the rest will happen as they progress).

TBH, I've not used the methods you've listed, so your mileage may vary.