Can you tell what the differences are?
You can definitely open issues in the Lemmy repo if there are any problems federation with other platforms. To publish the results of your testing you can also simply make a post in !fediverse@lemmy.ml or !lemmy@lemmy.ml. Doing this will be really helpful to make federation better.
What is this Snort and who is using it? Never heard of Meraki either. Anyway people who are affected by that can just sign up on another instance. And changing domains is not possible with federation.
Its the same for posts or comments, you need to paste the url in the search bar of your instance. For this you should copy the url from the colorful fedilink icon.
It sounds like you might be interested to host a new Lemmy instance. Right now the number of instances is still limited, and most of them cover niche topics. So it would definitely be good to have a Lemmy instance that is more mainstream. Hosting an instance requires some technical knowledge, but you can always ask for help in /c/lemmy_support or find someone else to take care of that aspect.
Creating a community on an existing instance is less effort. However it means that the instance admins have full control over your community, and you have to follow their rules. There is also no way to automatically migrate a community to another instance. Having your own instance gives you full control over the rules/moderation, and also lets you apply custom themes or change instance configuration (eg signup mode).
Thats not really how federation works. If you want Mastodon to render the data differently, you have to ask the Mastodon devs.
You can create a Lemmy account. If you are talking about Mastodon, you need to open an issue in their repo.
Thats not currently possible, you can open an issue. Or implement a bot which removes non-text posts automatically.
It would be possible to implement that (Mastodon has it), but there are no current plans to implement it in Lemmy. After all its easy to create a new account.