Mike,
What in the waveform is unimpressive to you?  "Inquiring minds need to know...."

A triangular waveform like that causes about 33% more loss in the motor windings than a nice smooth constant waveform would -- but that's just loss in the windings, not bearing loss, or loss in the ESC, or iron losses in the motor, or inefficiencies in the batteries.

Making it more efficient means switching the ESC faster, which increases iron losses in the motor, and switching losses in the ESC -- you'd be lucky if you got any increase, but if you want to start making ESCs you're welcome to try.  I'm pretty sure I'm not the only circuit designer on this forum; I'll certainly give you pointers (starting with -- start with a VESC and downsize it; don't mess around with rolling your own from scratch).

Alternatively, you could use external inductors to smooth the current.  That would add weight to the system, and you'd have to custom-make an ESC to deal with the inductance (you couldn't just shove it onto an existing motor).  Again, you're welcome to try.

ESC designers and their companies are a very very competitive part of this universe

IF there was a definitive way to reduce battery consumption and or increase motor power or efficiency....those experts would be highly motivated ....I think

It's a tradeoff.  I suspect you could, but only at the cost of a heavier, bulkier, more expensive ESC.  Whether the added ESC weight could be bought back with less battery -- I dunno.  Even if you could, it'd be a hard sell.