Played through most of this (49 rooms explored, looking in the editor tells me there are 54). There's a lot of good here, but unfortunately there are some things that are quite bad.
I'll start with the good. I like the focus on exploration. Going through rooms like 1W that have a promise of "
you'll be able to come back from a different entrance later to clear this"
feels good. Finally finding the way to reach that entrance and crossing it off a mental checklist feels great. There is some good attention to aesthetics; a lot of rooms look nice, there is variety throughout the level, and there are large-scale features like the corridor in the north rooms that make the level feel a bit more alive.
Most of the rooms ask players to do quite familiar tasks such as manipulating mimics or goblins, dropping trapdoors, clearing tar. But a lot of these feel like they have just about the right amount of stuff in them to keep the player engaged without getting overwhelming or frustrating. Rooms like 3N, 1N2W, 1N3W, 2N2E would be enjoyable for new players, and are still enjoyable for anyone who wants a break from modern linchpin puzzles and to relax with some good old-fashioned smiting. And 3N1W is an absolutely lovely multiple-mimic puzzle.
Now for the not-so-good....
Some rooms go on for too long. In 1S5E, for instance, there is a technique to clearing tar on trapdoors without getting stuck, and it's an interesting challenge to work this out -- but then you have to do a whole room of it and it takes for ever. I know it's hard to let go of rooms that mean something to you for personal reasons, but this one would really benefit from being trimmed down to about half as much tar. 1N2E and 3S4E have similar problems.
Overall, hidden stuff under tar was used in too many rooms, and it leads to rather tedious guess-and-check gameplay. I know this is built in AE so you couldn't use vision tokens, but in a room like 4E you could at least make the tar more constrained so the player isn't searching under such a huge blob. 3N2W is extremely tedious to search for the trapdoors while under continual tar baby harassment, and I gave up on this one entirely.
3E needs a checkpoint near the NE doors and one near the SE doors.
Going south from 3N2E will get the player stuck if they haven't cleared 2N2E yet.
Too many rooms had red doors. Sometimes they are used well, but for example, in 1S3E, 1S4E and 2S5E, nothing of interest is added by making the player drop all the trapdoors, and in 2S5E it's especially tedious. (1S would be another case but I didn't get that far

)
You need to be aware that the player doesn't know the level layout in advance and may not make optimal decisions. This was really driven home by 1S1W, where after clearing the room, the player is forced to go north. If they haven't yet gone west, getting back around to 1S1W to explore to the west means going through a number of rooms again, including two orb puzzles and a trapdoor puzzle that have to be redone. Similarly, if the player leaves the north section before clearing all the rooms there, to get back they have to drop all the trapdoors in 2N1W
twice more.
Finally,
according to HA rules the presence of a room copied from JtRH (even altered) is grounds for instant rejection.
Good luck with the hold; I think this could be a very nice hold with a little bit more work
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50th Skywatcher