“Global” post template

Hello WP-lovers,

I’m creating a plugin which then creates a custom post type.
The custom post type is mainly based on meta-fields.
Now, when I click on the link, to see my custom post, all I can see is the title. This makes complete sense to me, since the title field is the only “default” field I’m using.

I know that I can make a custom post template, and I′m aware of how to do that. The problem is, not everyone is using the same Theme. Is there ANY way, that I can create a custom post template (single) and make it work with the theme? I have spent hours thinking of a solution – and now I just gotta ask.

Can it be done?
If not – what CAN I do?

(I should say, I created some shortcodes to display the content as I want it – and that works fine. But what should I do when it comes to archiving? The permalink will link to the custom post type – and it’s empty ?? … Please help )

Best regards
Aris Kuckovic