Will GPG4Win ever support Elliptic Curve Cryptography? I know the development version (2.1.0 beta 3) of GnuPG does, but I can’t get that to compile in Cygwin, so I’m hoping that GPG4Win can, in the future, come with binaries that support ECC.
Failing that, could RSA key sizes at least not be limited arbitrarily at 4096 bits?
Hi Syntactic Sugar,
if a stable version of GnuPG support ECC,
the next version of Gpg4win will most likely also support it.
So for now you have probably watch the roadmap of GnuPG. 
As far as I know RSA are not limited arbitrarily at 4096 bits.
(For most practical purposes 4096 should be more than okay
and some security tokens may be limited.) Again this is something
you should check out GnuPG.
Best,
Bernhard
“…could RSA key sizes at least not be limited arbitrarily at 4096 bits?”
See here:
https://forum.gnupg.org/t/8192-or-bigger-keys/2646
Regards,
Sean C.