I've asked a bunch of questions on physics.stackexchange.com that I feel fall more under physics than electronics, but I'm not getting very satisfying answers. Should I just have asked them here?
According to the FAQ, this is the right place to ask questions about:
the theory and simulation of electromagnetic forces
Some of the questions you've asked on physics (such as the Radiation of LC Circuits question) would definitely be on topic here.
On the other hand, the Physics site has an active [tag:electricity] Q&A, and your questions seem to be well-received, so I think you need not feel any qualms about asking there, either.
If you conclude that that these questions are on-topic for both sites, then two questions logically follow:
When should you ask a question in this area on EE, when should you ask it on Physics, and when should you ask it on both?
There is a whole tag on MSO dedicated to this topic: [tag:cross-posting]. The general consensus is that it's OK to ask the question on multiple sites, but (1) don't ask the same question word-for-word, (2) be aware of the differences in the communities, and (3) give a question some time on a single site before cross-posting everywhere.
You should also consider where you'll get the best answer to your question. If the EE community upvotes your question and answers it quickly, there's little reason to take it to physics, and we won't force you to do so.
However, you may want to get the a certain angle (or multiple angles) in answers to a question. I won't bore you with the engineer-programmer-mathematician jokes that you've probably already heard, but we all approach a problem differently. You need to consider these perspectives when asking your question. It's unlikely that the same phraseology will be ideal on multiple sites.
Should EE continue to consider these questions as on-topic?
This is a whole new topic in itself. You may want to open another Meta question about this. However, I'll discuss it's relation to this question briefly:
There are a host of SE sites which cover overlapping topics. Examples include this set of questions on EE and Physics, and logical sets on Unix and Ubuntu, Webmasters/Webapps, Programmers and Stackoverflow, Mathematics and Computer Science, among others..