A change I personally would like to see is having battles take place in fp like in most other fp dungeon crawlers, instead of having that board with the character tokens overlay design you currently have(you could have that off to the side for selecting targets if it's too hard to program).
This would up immersion, which would in turn reduce the disconnect you feel during combat, which ultimately increases the feeling of tedium considering there's no feeling for what's happening on screen.
Other than the fact I like the style (Which is probably obvious from the fact I had tokens in Overlord H too
) that perspective is necessary because at some point it is no longer about the power of the individual enemy (except in rare occurrences), but the power in number. By himself, Bell is really powerful, but he can still get overwhelmed by a large number of enemies, and that will happen a lot in the middle floors.
A change of perspective would make everything feel too cluttered, it would work for maybe up to floor 7, but past that point there is the chance for more enemies to appear, and it only goes up from that point on.
Another would be to have encounters already on the map, rather than random battles. Although, that one's a real personal issue.
Most monsters are born from the walls, even in the LN Lili can quickly get out by following behind other adventurers/traces of recent battle because it is not really a matter of dodging monsters on the map.
another suggestion, although I have a feeling you're already set on this. Changing the linear class leveling into a more open one.
Such as a skills system(wizardry 6-8, elder scrolls, piranha bytes games, etc.), a skill tree system(I'm not a fan. But this would keep it far more faithful to the source), or any other system that gives you an active role in deciding how you want to level the character(I know he has a sort of set archetype. But there could still be options there.). Which Would give players an incentive, something to look forward to and work towards while grinding and leveling. rather than the grind feeling like a needless chore to overcome level gated content.
This can already be done by increasing certain ability scores, for instance if you were to get hit a lot at the beginning and heal, you would end up with a pretty high endurance score and once you get your first set of armor, you would become a tank.
Otherwise you can progress naturally, and you'll end up with a high dexterity score like in the source where you will dodge those attacks instead.
Later on you unlock your first spell, and you can start increasing your magic.
With enough money, and maybe entering Riveria's route, you could become a magic caster.
So, even if the system is really simple, you can already build your character to be one of the three main classes (Warrior/Tank, Rogue, Mage).
Of course, since this is possible, the best way is to simply increase all of them, but this is optional since the game is tested to be completable without any grinding necessary (aside from the monsters you need to kill in the main quests).
Another related suggestion. And this one could be another way to have progression without hurting the source.
opening up stores and having loot with different armors, trinkets, accessories, weapons(I know he mostly uses hestias dagger), enchanted equipment gems/crystals/orbs or whatever you wish to call them, that have different buffs and properties, with some enabling special skills or abilities(he could insert these into his weapon if you don't want Him changing it). This is the way hack and slash games like diablo and did progression to make "grinding through waves of enemies" fun and enjoyable to alot of players(I'm personally not a fan of hack&slash games. But, you can't deny the success and popularity of their mechanics)
This would be a way of adding personal touches, active player progression and personalisation/"character builds", without going against what's established in the series.
Equipment already exists: When you purchase your first set of armor, your defence slightly increases and once you get the Hestia Knife, your attack increases (and will keep increasing depending on your growth).
That is probably not very noticeable at the moment since Hestia updates your status when you get the knife, and the armor is a light one, however most people will feel the difference once they are left on floor 10 without the knife.
The equipment (should) also be visible, I would need to make the sprite for Bell with the armor, and then show said sprite only when Bell is within the dungeon. It is on my to-do list, he already shows with armor during CGs in the dungeon though.
In future another set of armor will be introduced (with another sprite), alongside Welf, and then other pieces of armor throughout the story (not necessarily following the source, but Eina might decide to gift you something else while you are in her route).
As for trinkets, they will be called "artifacts" in the game, and while they are not lore-friendly, they will allow the player to overcome some set limits (such as the number of spells), similar to Riveria.
Those will be some of the rewards in the secret areas of the dungeon (Alongside CGs/Events as mentioned in the tutorial).
And the final one. The dungeons are pretty bland to walk around as they currently are. Not sure how you would go about this, as I'm sure you have your own ideas. But as they are, they are mostly just endless hallways with random encounters, and a chest or 2.
I remember there being some secret areas(or were they story locked?) Which adds something. Maybe add some unique rooms, or special areas for each floor?
Dungeon floors are not that big, the first four floors are pretty straightforward and you need to go through them only 3 times before you can skip them.
During those 3 times, you can take small detours to discover small chests/side events.
Floor 4 is missing an event tied to floor 7 which removes the big rock and unlocks a hotspring for a CG (Wanted to do something similar to the OVA). Floor 5, 6 and 7 are missing events entirely, they are on my todo list.
Floor 8 and 9 have some events in almost each room, with the introduction of traps that will play a bigger role on Floor 10 and 11, which also have events/chests. Floor 11 has also the entrance to Nekoya Restaurant, an old easter egg from Overlord H which I am bringing over
The only thing lacking in all of them are puzzles/events that unlock the secret entrances, but otherwise they have enough events for their size.
Through the introduction of quests, you also get a reason to revisit them, with new events/objectives appearing.
Even main quests might add new events, for instance during chapter 5, you can discover the body of the unlucky adventurer on floor 7.
Last but not least, once I will add Liliruca's route, heart tokens will begin to appear for unique CGs with her within the dungeon.