I'm aware of them. And in a way, you are correct, the kissing
spheres is a subset of the regular vs. irregular tightest
packing series of questions. As I recall (and it has been years)
Solving the kissing problem in "n" dimensions leads to
solutions to the regular packing density question.
And this has now officially gone completely off-topic and
gotten rude so that's it for me on this topic.