Howa.

It already has about the strongest extractor you can get on a push feed bolt.
The receiver is a flat bottom design which lends itself to better bedding than a round receiver.
The recoil lug is a tapered design integral to the receiver.
After market triggers are available from Timney, Jard, and Rifle Basix.

The only down side to doing a Howa VS. a Remington is that the Howa has metric threads and some gunsmiths lathes are not set up to do metric threads.

Gunsmiths like to use the Remington because they are absolutely every where, they're cheap to acquire, and a round receiver is easier to work on than a flat bottom receiver. They're kind of like the Chevy camaro or Ford mustang of rifle actions. But that doesn't mean they are necessarily the best action to build on.