I'm consistently surprised that airlines have yet to launch plane lines featuring business class seats / service throughout the cabin on select routes. I would assume that it would be easy to fill such a plane a few times a day with reasonable rates across east coast commuter routes and from NY to London.
Every row of 6 now becomes a row of 4, and the spacing between each row increases by 33% just in seat pitch alone. Business class seats are also larger themselves, so the difference in row depth is probably more like 50%.
So 30 rows of 6 economy class seats each = 180 passengers now becomes 20 rows of 4 seats each = 80 passengers.
You have to more than double your fare to break even.
You can probably fill planes in this configuration, but the question is at what frequency? Scheduling is intensely important to air travelers, and a luxurious plane that only flies once/twice a day and has little schedule flexibility is a non-starter. This is especially true domestically in the US, since few journeys begin/end at major air hubs, making scheduling connections a pretty big deal.
Your luxurious aircraft will mean a long layover, not to mention your connector flight probably can't get enough volume together to also be luxurious, so at best you're only getting the premium experience on a single leg of the trip.
This is also why comparatively "luxurious" airlines like Virgin America are struggling. They do not have the scheduling frequency nor the variety of destinations that American travelers demand. It turns out you really cannot just build an airline out of major arterial routes.
SQ used to fly a non-stop LAX/EWR to SIN flight with 100 business class only seats. I've been on it once and it was filled maybe 40%. They killed the route last year.
