Most of the problems come down to the fact that people aren't really playing it for the game but to unlock the sex scenes. This game does have a few bugs and the walkthrough has minute errors, but nothing that should warrant it being called hard or buggy.
Only thing I'd say that needs work is the time skip and sleep functions. Time skip so that we can skip longer periods of time if we're stuck at a "waiting" portion of a quest (such as Penny's non-corruption route). Sleep function cause I just want a good, dedicated bed to sleep in without fear of getting jumped by one of the harem members. I know we got one in Penny's house but I'm talking about a bed like Emily's which has "bed comfort 3". Maybe we could see that when a carpenter shop or something opens up.
Edit: Another would be scaling battles. While scaling battles are good for exp, I'd like to actually be able to fight bandits without needing to bring Tia or Lyvia with me. Feels weird I can take out orcs and plaquefiend's relatively ok but human bandits are giving me trouble. Maybe buff the damage on weapons or add more defense for armor.
For a bed with bed comfort 3, we probably will see that in Marcus's hut when Gwen's update wins and gets implemented, since that will come with upgrading the house.
For battles, if you get high enough in levels, eventually the enemies stop scaling (except a certain special hidden boss). Also, armor can be upgraded by adding plates, and if the armor you have doesn't get any slots, or only got one, you can craft another until you get one with two slots to add plates to. Besides that, if you add Talent points to the Armor Talent, that will also increase the effectiveness of armor by percentages, and eventually allow for equipping heavier armor like chain mail. Can't recall with damage on weapons, but doesn't the Strength talent make the MC stronger in combat? And then a couple other Talents help with criticals. So there are lots of things to do there to make the MC better in combat.