Those themes you listed are all covered well (and clearly so) in his many short stories. The novels, on the other hand, are obscure and meandering with often too many characters who are lacking obvious relevance or role. Also, too many themes are often intermingled and often not expressed very clearly and only obscurely alluded to.
I am certainly not a critic of PKD’s themes – he is perhaps my favorite science fiction (depending on how you define it) author when it comes to short stories. I’m just saying his short stories works much, much better than what resulted when he tried to write longer works.
(This is unfortunate, since many people, when they hear about PKD, think “I’ll pick up one of his novels” and immediately get something like “Radio Free Albemuth”… and then never read something by him again. My aim with my comment was to get those people to try his short stories instead. PKD, unlike most authors, should not be considered a writer of novels, but of short stories.)
Radio Free Albemuth. Not exactly his best novel. Yes, if someone picks some random Dick novel, he's likely to be disappointed and your criticism of such a random Dick novel stands a good chance of being correct. I think the same could be said of random Dick short stories as well.
Setting those aside, I think your argument is harder to make where his best novels are concerned.
That said, I'd be interested to hear what you consider Dick's best short stories. Most of the ones I've read have been pretty disappointing (with the exception of a couple I cited elsewhere in this thread).
I am certainly not a critic of PKD’s themes – he is perhaps my favorite science fiction (depending on how you define it) author when it comes to short stories. I’m just saying his short stories works much, much better than what resulted when he tried to write longer works.
(This is unfortunate, since many people, when they hear about PKD, think “I’ll pick up one of his novels” and immediately get something like “Radio Free Albemuth”… and then never read something by him again. My aim with my comment was to get those people to try his short stories instead. PKD, unlike most authors, should not be considered a writer of novels, but of short stories.)