The new features in 0.3 and 0.2b help a lot with navigation.
The quest log is very useful and I feel like it will be even more important as the game grows. It gives a good anchoring point to help players decide what to. I looked through all the rooms but never did find how to start the "Dirty Worshipper" quest, so it might be worth listing the areas in which each quest can be started. Maybe display it as an "unknown area" if it's never been visited to prevent spoilers.
I like the idea of the guest list a lot. Having something specific for players to look for is a very welcome addition to an exploration themed game. I think they're added automatically for each area you visit, but it might be fun to have the players click on them instead. You could also use the guestbook to show the transformations and which characters fuse with others. It wasn't immediately apparent to me that "w" and "s" keys scroll through the guests in each area, so a small indication of the keys may help.
The map does take away some of the mystery of the game, but I think it's a good addition. Maybe offer it as a quest reward similar to the guest list to encourage players to think for themselves a bit more at the start. I like that it has a basic look and doesn't give too much away. The one thing it needs is some sort of indication for your current position and maybe a way to open it quickly with the "m" key.
I enjoyed the adventure elements that have been introduced over the past couple of updates. They make the game feel more interactive and encourage purposeful exploration. Thank you for the update, I had fun!