Sorry for the late reply.
1 : The speaker will be a large standmount and a closed box design.
2 : Price is still up in the air but will be well under $1000. Probably in the $700 to $800 range
3: The speaker is passive for now
4 : Efficiency will be rather low about 87dB and will handle 100 watts easily
5 : Frequency range will be 42 to 20kHz
6 : Nothing drove me away from single driver speakers. I prefer them to any other design. This speaker is still using a single driver full range, but with a little help from a 10" woofer. I wanted to design a 2-Way speaker that lets me set the crossover point well away from the critical midband and using a full range allows me to do this as well as being able to incorporate a 10" bass driver instead of the typical 6.5" & 8". This speaker is similar in concept to Martin Logan Hybrids, but using cone type drivers.
This speaker will be under the Marathon name and best used with more powerful PP tube and SS amps
6: Can't tell you how it compares yet as it's still under devolopement.
Thanks and I'll post the progress.