Ok, now that the Electro 7 manual is out.
The Electro has dual oscillator going to a single filter (not possible in the wave2) with options to detune and mix as you want.
No PWM though.
The FM implementation is amazing. Like actual individual control over all operators.
Samples yeah, the same.
Extended analog and wavetables not present.
Why couldn't they do the same for the Wave 2? It is beyond me. Just detuned saws, it is not that big of an ask, literally the most used oscilattor configuration in synth history. And the FM implementation was so lackluster.
There is enough processing power to do that (hence the huge voice count of the wave 2).