Thanks a lot for the throughout feedback!
The corridors indeed are very similar optically, unfortunately we only had one 3D Environment Artist to build it all.
We tried to make sure that the Wrench wasn't hard to miss, it definitely took us some tweaking, we didn't want to make it too obvious (and hence too easy), fists were implemented, but eventually removed because of balancing reasons.
A locked camera is really something unusual to get used to, overall we kinda wanted to stick to the classical Dungeon Crawlers way of input and moving around :)
Hopefully we will find the time to implement the additional levels in our free time, at least that's something we are planning to do!