May I offer up this the 1985 SciFi Enemy Mine (https://en.wikipedia.org/wiki/Enemy_Mine_(film) )? It is an excellent adaptation of Barry B. Longyear’s novella of the same name, Directed by Wolfgang Petersen (of Das Boot fame). It had a low budget (40 Million) and its special effects are well, dated even for 1985. Excellent acting by Dennis Quaid and Louis Gosset as the principals. Bombed at the box office as it was Neither Star Wars, Dune, nor Wrath of Khan.
I would also like to add in the war film department the 1969 film Battle Of Britain . To say the storyline is weak is an understatement (although it is briefly redeemed by Susannah York prancing about in her knickers). The killer here is the aerial fight scenes. These involve LARGE numbers of actual Spitfires, Me109 and Heinkel 111 aircraft (Me109 and Heinkels being part of the Spanish Air Force). They are well scripted and had input from Douglass Baeder and Air Marshall Dowding. It has a G rating but some scenes are almost too realistic and freaked out the 8-year-old me, who dunned my dad into taking me to the movie.