become-operational for me seems nowhere near as slow:
ubuntu@ubuntu:~$ snap debug timings --last=become-operational
2019/07/16 15:49:38.751216 cmd_linux.go:224: DEBUG: restarting into "/snap/core/current/usr/bin/snap"
ID Status Doing Undoing Summary
98 Done 350ms - Generate device key
^ 343ms - generating device key pair
99 Done 285ms - Request device serial
^ 239ms - get device serial
^ 152ms - prepare device serial request
^ 87ms - submit device serial request
^ 30ms - fetch signing key chain
I’ve uploaded snap debug timings --last=seed separately since it is huge; the only thing that sticks out to me as being singularly large is
8 Done 35875ms - Make snap "core" (7270) available to the system
otherwise a lot of the connections take ages to be made, which probably adds up. Also this confirms that gtk-common-themes was set up after the applications were.
And I’ve uploaded the journal too. You can see
Jul 16 15:46:45 ubuntu systemd[1]: Starting Wait until snapd is fully seeded...
and
Jul 16 15:48:15 ubuntu systemd[1]: Started Wait until snapd is fully seeded.
to indicate how long it took.