But I use Lightroom every day, and you might be faster but you aren't working at the same level of quality.
I loaded up a 16-bit TIFF and got an 8-bit JPEG as a result, which leads me to assume that you are downsampling to 8-bit to work.
Also, the results in polarr are way harsher then Lightroom, which is pretty common for non Adobe products. GIMP is especially harsh in contrast to Photoshop.
But even before getting into the color correcting stuff, you're already shifting color (I'm assuming you are ignoring the embedded color profile in the TIFF):
http://i.imgur.com/QKb42l5.png
Also, Lightroom is way faster making adjustments. I can see polarr "thinking" when I make adjustments (it gets pixellated and then clears up), while Lightroom does them in real time.
I couldn't get your curves to work.
No split toning.
Lens correction should be automatic and profile based. Lightroom will automatically fix distortions based on Camera and Lens model. Same with basic color calibration.
Again, I don't want to be discouraging, but I find the hyperbole kind of frustrating.