Most comfortable handle?

[TrainedBullets]

For me, Fiddleback Forge Sneaky Pete. The Big Sneaky is closer to your size range (same handle).

 

[herisson]

Simple straight handles win any time over contoured (overthought) handles in my book. Just some examples :

 

[Gary W. Graley]

As a few others have mentioned @Nathan the Machinist aka Carothers have about the best and very secure handles, this one is his EDC model designed by @Lorien

Nathan_Carothers_EDC by GaryWGraley, on Flickr

Nathan_Carothers_angle by GaryWGraley, on Flickr

IMG_6170 by GaryWGraley, on Flickr

G2

 

[eveled]

Any Buck 100 series has good ergonomics.

For a fighting knife. The classic KaBar stacked leather is hard to beat.

Can’t go wrong with Becker either.

The Becker BK62 Kephart is very comfortable to hold.

 

[kwackster]

Currently busy finetuning two Condor choppers, a Bushcraft Parang and an Eco Golok machete.
For years i've only used kukri models for trail clearing (a Tora Blades Camping kukri and a Cold Steel Kukri machete) here on the Veluwe, and the plan is to get some hands-on experience using a few other tried & true chopping blades from different parts of the world.

Just did the contouring & fuzzy/chewy finishing of the Golok machete handle with the wood rasp (the Parang will get the same treatment), and tested the blade on a few thick dried oak branches and various green branches.
Very well hardened 1075 steel i must say (no visible flattening or rolling at +/- 30 degrees inclusive), and now the handle is much more comfortable and grippy compared to the thick and slick factory handle (for my hands anyway)
Also no need for additives like grip tape etc.
Both will receive a narrow convex edge later.

 

[fielder]

Of my knives four stand out for comfort. The Spartan Harsey Hunter, Bark River Bravo, Busse Meaner Street and Survival Lilly Apo 1.

 

[evilgreg]

I can carve wood for hours with these:

 

[scottyj]

My Bark River Bravo 1 fits my hand like an extension of my body.

 

[Jcsixx01]

I’m a sucker for sculpted handles on fixed blades.

 

[hhmoore]

The Bravo handles are a little small to be comfortable for longterm use, at least in my hands. A little more height or thickness would help.
Becker handles are pretty good, as are Esee (esp with a little reshaping or TKC scales)
Ontario handles, at least the ones I've experienced, suck until they're reshaped.
Busse handles are hit or miss for me (mostly miss)... but I like the Urban Grudge and Ratmandu (though they're smaller than your target range). Their Res-C handles are comfortable, but a little thin.
Carothers handles feel great in hand...but I haven't put the aforementioned HDFK to use yet (I took it in trade, intending to sell it; but haven't been able to bring myself to do so).