Wonderful sculpting, John. And I agree, that Doughboy, there's just something about him that's really appealing.
I haven't worked in 75mm scale yet, but plan to as soon as a couple of projects are completed. I agree with Alex, it's a great scale!
As far as conversion accessories in 75 - 80 mm scale - how about Fusilier? I don't think he's made any Springfield rifles, unfortunately. Once they were in theater, a lot of (I believe most...) US Army and USMC were required to turn them in and use Brit SMLEs for ammo supply reasons. And from what I've read, the US soldiers thought the Springfield superior to the SMLE, except for field durability maybe.
Question - It may be the photos and the typical size distortion that can occur due to lighting, etc., but, to me, the helmet on the Doughboy looks a little too large for the head? Not much, just a little bit.
All the best,
Dan