I don't really have a horse on this race, because until the game is more completed I'm not going to try it, I already have enough games that I just WANT to play, but because they are in beta I get frustrated once I reach the end, but...
I don't remember explicit hints, object highlighting, compass, map or objectives tracker in Dark Souls series. Apparently, those are bad games too.
Then you haven't played Elden Ring, aparently, or at least haven't paid enough attention. Some of those things that actually worked (to a degree, they were still extremely esoteric sometimes and only really worked because of the community behind, not just because of the game itself) in Dark Souls didn't work so well in ER, so they had to add some markers for quests and all that, and I'm still asking for a mission log, so at the very least I can check what quest I have active and what's the last step I did, because the games is too fucking big. A bestiary would be nice too, to check which enemy drops what when I'm farming for an specific resource.
It's not an universal solution, sometimes a game NEEDS them, and sometimes don't. And sometimes they need them, but the developer did a job so well done that it is faily intuitive without them, or more likely, they are there but the player doesn't notice them, but that's the exception, not the rule. When in doubt, assume you are not the exception.
Some of the BEST games of all times actually use them, but they either integrate them in story (Horizon Zero Dawn), or their hints are subtle enoufh (BotW, TotK) that they aren't disruptive, but help locate what you need that would otherwise be skipped by most players.
My advice? If your players are telling you that they are too hard to find them, look into it and don't try to be Miyazaki. Aonuma is also a perfectly fine model to follow, to the point MIYAZAKI himself followed him with ER. There is a reason why the point and click games now have a button to show the player what can be interacted with, after all (there are very few things as frustrating as looking for the PIXEL the developer decided is the logical thing to interact)
I'm not trying to make comparisons, but layout of my level is so simplistic, it doesn't even have any verticality, I have no idea how one can get lost.
Verticality doesn't equal complexity, complexity equals complexity, as obvious as it may sound. A game with verticality may be also extremely lineal (Valkyrie Elysium comes to mind, very linear, but have verticality), and a game with just xz axys may still be extremely complex to navigate (a lot of old games are like this, between lack of map, lack of identificable points, etc). Is your game like that? Again, no clue, just mentioning it, so you can check and decide. When in doubt, though, I recommend to lay on the side of "Make the players time with my game easier", it helps to keep them invested in the game.
Traversing with greater speed, teleport skill or flight are not compatible with the theme of this game.
On one hand fair, some games require to be... slower. On the other, I advice you to look into if you can make the game a bit easier to traverse without breaking the theme of the game. You'd be surprised how much frustration a bit more of speed while travelling can take away from your game.
All of those advices are general recommendations from my experience playing through all my life (since Super Mario Bros, so I do have a bit of experience xD), and my intention is for you to check it again and decide if you are really right or no. Of course, too many cooks ruin a dish, so at the end of the day its your call and you shouldn't change everything people tell you to, but I think you should at least check, just in case they are right. If you are right, fantastic, nothing to change at all. If you aren't and pay attention to those recommendations your players are giving to you, that's a bullet you dodged.
So, again, check it out. Or better, ask someone you trust to check it out for you (key words there, "someone you trust"). There is a reason why the developer shouldn't be the beta tester in any game, and it's not just that a beta tester is trained to notice the misteps and bugs of a game, where it works and where it breaks. The developer knows how their game works, and, unconsciously, will accept and do what the game is programmed to do, instead of looking for where it breaks, and will have a biased opinion on how good it feels to play, instead of a more unbiased and general opinion (that's also why there is not just ONE beta tester, it should be a big group with different kind of players, but I understand that's much harder to accomplish for an indie developer : P ).
