What applies for Austria applies for Czechoslovakia. But here, timing of the events that trigger the step by step taking of the country is decisive. Watch yourself, or the Allies will declare war on YOU.
Denmark is the connection between Scandinavia (specifically Sweden) and Europe (primarily you). Also it has the region that is used to block off the Baltic Sea-North Sea connection. It is tactically a high value target. It blocks Britain to deliver naval help to Poland, it blocks the Soviet Union's Baltic Fleet from leaving the Baltic Sea. Also, the fact that several waterways split the islands and the peninsula from each other makes the country easier to defend (also bear that in mind when invading Denmark). Denmark is a so unnecessary target from bounty standards that just inviting the country into the Axis will make no difference at all.