This is loosely related to "online experience" (as you've covered most of the "tech tips") :
When choosing a movie don't watch the trailers, instead (blindly) watch what's popular. (obviously, if you're into niche genres - this won't work.)
I've found Trackt is a good place to understand recent trends (and it just shows film posters). Then I'll go to IMDB, maybe read the summary, but I always read the first/popular user review and decide if it's worth my time and money.
The first/popular user review usually doesn't contain spoilers.
Since I've actively avoided trailers and spoilers, my enjoyment for films has nearly doubled - even for "bad movies" (I probably wouldn't have watched otherwise). It's such a shame that a 2 minute trailer often shows many/most of the highlights of the film.