Yes, I would definitely recommend that. If only because that's how virtually all networks with VLANs are setup and if you do something unusual like that you will hit unusual problems!
Really the only reason to trunk tagged VLANs to a host is so that host can access multiple VLANs. So you might do that for a VM server or an access point with multiple SSIDs.

Steve

Hey there,
I think the problem is not within the Router but in the testserver.

Even though I did a reinstall recently and never installed anything else than apache2 and openssh-server, a tcpdump confirmed that the packets arrive at my testserver but my testserver does not respond to them for whatever reason. So most probably my fault.

Anyway

Thank you @Rico !