I went even funkier and tried it with a spare 20 inch front wheel and fork I had laying around. They don't fit but it gave me a rough idea of how it looks and what the angles are like.
Even with the 20'' I still have decent ground clearance even with my short cranks although 24'' would prevent any pedal strike issues.
With the 20'' fork and wheel seated, the --previously-- sloping toptube is now completely level. The angle of seat tube is not completely vertical but definitely a lot straighter.
The whole bike is significantly lowered and so is the BB height. The chain angling downwards. The position feels awesome, I feel much closer to the ground, I can basically look recumbent bicycle guys in the eyes! I think it would be hella fast , with much less draft for guys behind.

It might look dorky to boring people who don't dare to challenge conventional standards, but once you understand my reasoning it actually starts making some sense.

Of course a frame with a lower BB built in would simply give me what I look for as well, but these frames would have to be custom.

Going to two 650B wheel would also lower the bike a bit, although not that much, and require vastly more expenses and investment.

Of course two 24'' wheels or smaller would significantly alter the whole gearing and introduce more expenses, including requiring disc brakes.
So only swapping out the front wheel and fork makes sense, and possibly a longer stem -- for what I am trying to achieve !

The simple fact is that once 140 mm cranks become your '' standard '' , the whole frame in essence has to be redesigned, or you have to deal with a significantly higher saddle height and thus center of gravity and catching more wind.
The bottom bracket with 140mm cranks can simply be a lot lower. Low is aero and safe.

I am definitely going to do backyard experimentation with this as time goes along but I am not gonna throw a lot of money at it.