Making this list would take about 20 or 30 years.

Narrow it down to three movies or TV shows or books.

Planet of the Apes from the original movie series with particular attention to the original 1968 movie and the first sequel Beneath the Planet of the Apes.

The Ape Army should receive special attention.

Set 1: Gorillas mounted on horses.
Set 2: A jail wagon and a cargo wagon, pulled by one horse each with gorilla driver.
Set 3: A gorilla artillery piece with limber, driver, horses and crew.
Set 4: Gorilla infantry / police with various carbines, submachine guns, flag bearer, and cameraman.
Set 5: Orangutans in various poses including seated, standing, reading a scroll, riding a horse.
Set 6: Chimpanzees in various poses similar to the Orangutans, but including females and young ones.
Set 7: Humans in astronaut garb, but mostly as wild humans eating, running, standing, male and female and young ones.

A single "generic" set of the main characters and a selection of other Apes could be done to gauge the interest in such a set. I would think the sets could be done that are similar to the movie characters but not close enough to infringe on copyright, not unlike sets of elves and such are similar to other movie franchises.

A set of generic spies and henchmen not unlike the James Bond movies would be useful. Men in tuxedos, trench coats, women in evening gowns, henchmen with the MP40s, AK47s, and M16s. I run an Airfix plastic figure group on Facebook and James Bond figures are the #1 requested figure line to Airfix on that group of nearly seven-thousand members.

Mike Bunkermeister Creek

I agree Mike, this is a too long list with a lot of very niche ideas. Most of it much more suitable for a small metal or resin figure manufacturer who could cast on demand. I reckon Planet of the Apes, Star Wars like and Starship troopers like sets might be a goer. Would be nice to see Starship Trooper like bugs or the classic xenomorphs from the alien movies. Of course, all of this might have insurmountable intellectual property issues. I've been contemplating getting the space devils from Khurasan (I think) but at a nominal 15/18 they might not look that menacing against 20mm figs.

Action Fleet did Starship Troopers and Aliens and Star Wars many years ago, their stuff is still sold in eBay and it's very nice and durable. They were sold as toys and so have a lot of play value. I got some when they hit close out in the stores. The are about the size of "large" 1/72nd scale figures.

There have been a lot of Aliens toys out there and not all of them were licensed. The general shape of the alien seems to be okay to make without a license, but I am no lawyer so don't listen to me.
But how large is an Alien? So they are around if you look for them.

The nice thing about the Action Fleet stuff is all the figures and vehicles are the same scale. You can use Starship Troopers to fight aliens or Imperial Storm Troopers.

Just do an ebay search for "Action Fleet" and they will show up.

Mike Bunkermeister Creek