I've finished Return to Eden (with help of a walkthrough). It turns out that this game has a sprawling map, with room descriptions unfortunately consisting of a single line ("You're in a long tube"), more if you're lucky - but all that's likely due to lack of memory on microcomputers of the time (1984). Scenery can generally not be examined, though carried objects can. It's well known that Level 9 advertised the first installment of Silicon Dreams as having "over 6,000 rooms" which turned out to mean 4,800 rooms that are exactly the same, but in Return to Eden they've pulled all the stops to create a gigantic map, with well over 200 rooms.
For those who have read the accompanying novella, Eden Song, describes mostly the city you'll encounter in the sequel, Worm in paradise, but Return to Eden expends some effort in letting you roam the city under construction, and under robot management. As such, there are no characters you can speak to, only robots - and any conversations are once-off one-liners. Robot city has a few locations where the Austins put some humor in the game, where they could afford to spend a few bytes. There are a few funny references comparing the future that Return to Eden describes to the year 1984.
One thing of note is that this game hardly contains any puzzles (beyond mapping it all out). Most puzzles are solves automatically if you're carrying the right item. Thus, picking up everything you come across is enough to solve the game. It's too bad there's an inventory limit, which requires you to go everywhere with a different selection of objects just to see what works.
This game is from a time where mazes were still considered an essential component of an adventure game, and this game offers two (or even eight or so, if you count all the sections where exits are one way or loop back), both of which be solved in the most straightforward way. They're not very big, thankfully.
The game's ending is a bit of an anticlimax: you're rewarded with two lines of text that essentially say, "you won", and not much more. Showball did a better job of building to a climax.
(It may be useful to someone trying to play this that in my playthrough, a certain casino was broken. I needed to use CheatEngine to give myself extra money, although the walkthrough and Level 9 Cluesheet insisted that this wasn't necessary; for me this made the game unwinnable.)
Here is a map to Return to Eden.