A: Hello

Difference in "New content ideas" between Silver and Gold plan:
A. In Silver plan you can add ideas manually, and creating content calendar with this ideas.
B. In Gold plan, you can add ideas manually and they can be created semi-automatic using best available content for specific topic thet your competiton covered and you do not covered yet.

Here is more details:
https://www.youtube.com/watch?v=OiQV1dj0_Bs&list=PLtkFbQwk71gEXrGpJRtxq6tGhbp_dyxrs&index=8

Hope this helps ;)