Use all forms or define "no request type" when creating issue without portal

[Jochen Betz]

I've created 5 different forms which are used used in 5 different request types accessible from the portal. Each of them focus on a different aspect of a problem to be reported, thus have different fields available. But they all end up in the same issue type.
When created they fields are organized on 6 different tabs. 1 for each from and 1 general one.

So far that works.

But: I also need the possibility to create an issue without the portal. But in this case, the request type currently always defaults to "Email request".
I cannot find a way to specify "no request type" as the default request type.
Neither can I create a new request type and set it as default because the new type can only use one out of 5 forms.

What I can do is to manually select "no request type" each time which gives me back the 6 tabs. But this is a useless step to bother with every time.

Are there any solutions/suggestions I missed so far?