I wouldn't be afraid to go with any you listed.
I do lilke the new Defiance actions. The all one piece bolt is a plus.
I believe the least expensive is the Lawton.
Kelbley also has a new 700 clone out.
There is a writeup in last months Precision shooting magazine on the Bighorn.
It has a floating bolthead like the Savage if that trips your trigger.
I don't know any thing about the Bighorn. The Lawton is the only action you listed that I would not use at the present time due to the number of quality control issues as of late. I agree the Stiller is very good and probably the best bang for your buck. I used the BAT HRPIC to build my 338AX . The BAT is excellent. All the others you listed are excellent and I would build on any of them. It will come down to what you want to spend, single shot or repeater, weight etc. All have different models and you should discuss with your smith exactly what you want to build and spend which will make your action selection much easier to narrow down. I do agree with your ratings of the actions in general and really with them it is just personal preference.