Larry Horsfield has put up a new website which bundles all the latest versions of his games.
I playtested and reviewed a bunch of the Alaric Blackmoon games. They come to my aid in my longing for long and complicated, earnest and non-ironic Fantasy-quests. Each one is playable on its own, but you might as well start with Axe of Kolt, the first Alaric-adventure.
I haven’t played any of Larry Horsfield’s science fiction games yet. If they’re anywhere near the Alaric-games, they must be good too.
I played all of his fantasy adventures and all of his sci-fi games back in the ZX Spectrum days… They were pretty huge epic, spawling multi-part games back then (especially given their humble Acorn Electron roots) so I can only imagine how massive the Adrift versions must be. 
When I was searching for hints/walkthroughs for the first Alaric-game, I stumbled across a few walkthroughs for the ZX versions. Apart from a few recycled/updated puzzles, they’re very different games from the ADRIFT versions.