Although not on my list, they're both good movies, probably because they deliver unexpected touches, at least if you saw them when they first came out or didn't read up about them in advance.
Assault was Carpenter's second feature, and since his favorite director was Howard Hawks, what better thing for a young filmmaker to do but remake
Rio Bravo with very little money and lots of weird, eerie touches. You should know if you're a policeman to never go anywhere near a precinct numbered 13! Well, Precinct 13 is closing up shop and a skeleton crew has to make sure that it goes down quietly. Trouble is a busload of criminals stops there at just the same time that some wacko killers go on a rampage in a strangely-vacant part of Los Angeles. So you have a set-up which superficially recreates
Rio Bravo while all kinds of weird stuff goes off in Carpenter directions. The most-notorious of these is the ice cream truck scene which painstakingly sets itself up and then pays off with violence which seems far ahead of its time (and follows that with an exciting, if ridiculous, car chase). The actual assault does contain more strategic violence and an accurate portrayal of Hawks' macho men sacrificing themselves while kicking ass, which of course is one of Carpenter's favorite themes too. Just look at his version of
The Thing (another Hawks remake) and
They Live for proof. One last thing I'll mention is that this film reminds me at times of Romero's
Night of the Living Dead. A small, isolated group of people, led by a strong black man, is attacked by a group of crazed killers. Carpenter chose his progenitors well.
The Wicker Man was already a cult movie when it was released in the U.S. in 1975. Yes, it took a year-and-a-half to reach our shores. The advertising played up that it wasn't a typical horror film, that it was more about a clash of cultures or religions. It was pitched as a mystery though, so the uptight Christian police sergeant played by Edward Woodward gets more than he bargained for in the Scottish Hebrides when he investigates the disappearance of a girl. There are uncooperative locals and the upcoming May Day Festival for the sergeant to deal with, but he's especially disturbed by the wanton desire and preoccupation with sex found on the island.
The Wicker Man does have a connection with many of the Hammer Horrors that dealt with bizarre cults, but it takes it a step further and also supplies an abundance of local color and music. It seems so well-researched that it could be a documentary. If you don't know what it's really about, the long, detailed ending should hit you really hard, but I suppose there's always a chance that some viewers will laugh at the goings-on. But then you can always find people who will make fun of others' religious practices just as much as they'll make fun of others' favorite movies - not that any of that ever happens here.