1 - I would use a FStruct and put the floats/ints inside.
2 - The engine spawns a PlayerController marked as default on editor settings by itself.
3 - There are some answer about this somewhere, I think that is because of both, but some people (search) was also using a plugin to speed intelisense.
What if we look at #2 in a different perspective? Like a portal or something?
If I write the behavior for the portal in C++ would I be required to create a Blueprint of it to be able to spawn it?
EDIT: In the “Choose Parent Class” dialog I can only seem to be able to find a “UserDefinedStruct” is this what I’m looking for?
No.
“BUT” get a Blueprint from it could help a lot to design the visual elements (Components) used on it (Sprite, Mesh, Particles, Mess with positions of each on a WYSIWYG way).