So. I played several times. And I think the game is ruined for general public. Maybe hardcore players can enjoy this.
Here is what I think. Just like lots of games in the past the game is made with a player in mind who already knows the game really well. Not for a first time player who have no idea where to go and what to do and why and how.
For a general player here are some things that blocking good game experience:
1. Respawning enemies. I don't know what would be best to do with that. It also ruins fun of exploring the maze.
2. Timer.(health going down) it's just one of the worst things in games from the past.
3. no map access. Why not give a map like all the best games out there do?
4. opening closing doors. I understand it goes from the urge to increase difficulty, because when developer plays his own game he doesn't feel it the way when first time player playing. So he thinks, oh it's too easy and adding something to add difficulty that he could feel.
5. items unresponsive to take. I had problems to pick up items.
6. Also the items gotta be visible on the map. As we have to drop some of them.
7. Maybe save points. Not sure tho.
I am not some unskilled player, by the way. I played and beaten many NES games. Their difficulty is way above average of todays games. Spectrum? Not so much. I did not had one at home.
If you want to bring in all those frustrating things - just add a hard difficulty and throw all that challenging stuff in there. Why not give general public to enjoy the game on a normal mode?