2.4 inch 29er Tire recommendations and inserts.

Hi, I'm planning on getting new tires to replace my Goodyear Newton ST EN Ultimates once summer comes.

I find the 29 2.4 Newtons to be extremely grippy (I'm planning on using them exclusively as my winter tires), well-damped, and strong enough to be run at really low pressures. They also hold air really well without sealant. However, they have an insane amount of drag at the low pressures I prefer. While the amount of drag is tolerable on trails, I don't think I can take it on long bikepacking tours.

I've tried out 29 2.4 Maxxis Ardent tires and found them to be really fast, grippy enough on the trails I ride in the summer, but way too stiff.

I've also tried out the Specialized Fast Trak Control 650B 2.3 tires and liked them. Not as fast as the Maxxis Ardent but much more supple. They were a little bit weak, though.

What's a good supple tire with low rolling resistance? I need good grip on hardpack and pretty much nothing else. Riding conditions are mainly hardpack trails and long distance backpacking on bad roads. Puncture resistance is an afterthought because I have never had a puncture too big for the sealant.

My current most convenient choices are:
Specialized Fast Trak control
Specialized Butcher Grid
Teravail Ehline
Teravail Honcho
Teravail Sparwood (a bit narrow but I can tolerate that as long as the tire is supple enough)
Vittoria Mezcal 3
Anything else from Vittoria
Anything from WTB

Less convenient choices include anything from Schwalbe and Continental.

Do you think a tire insert will bring much improvement?