A brief feedback and suggestions (edit : not so brief).
I really like that you're adding a story and making the npcs more interesting (tenants and family).
The achievement system is a great idea, you could do a lot of things with this, not just the tiers you're doing right now (which are good already). It could be a way to unlock rewards. Money, repair kits or gift for the easiest achivements, new outfits for the tenants and maybe achievement exclusive tenants for the more difficult achievements. Achievements is a great and easy way to provide goals for players.
These achievements could be like the ones you already have, but not tied to a tier, they would be available at all times. Example of achievements could be like the ones you already have (get X tenants at Y intimacy/obsession) but also since tenants have many specific traits you could use them. For example get X tenants between 18 and 23 years old (maybe add stats values for more difficult achievements), instead of the age, you could also use the continent of origin (it's already showing at the airport, so might as well use this). And I'm sure you could come up with other types of achievements and rewards, in addition to the tier system already implemented.
About the free version, having only 2 hacking slots is really hardcore (but maybe it's because I like to play with multiple simultaneous tenants). I played previous free versions where the hacking slots weren't limited, which allowed me to progress nicely in the game, but if I hadn't and played for the first time with a 2 hacking slots version, I might have just stopped playing. Since I'm obsessed with achievements, maybe the free version could have a few achievements allowing them to unlock a couple more hacking slots.
And it's great to have the beach available in the free version ! Also, the dual tenants date system (volley ball) is really nice. A suggestion about this : it would be nice to have some eye candy during this double date. A picture of the two tenants together in their beach outfit (or less...). Of course, considering the amount of tenants you couldn't do all the combinations, but it would be a nice surprise to have some. I have no idea how time consuming it is to make a quality picture so maybe it wouldn't be worth investing a lot of time in a minor feature.
About the Lucky Dice being replaced by mini games, I'm concerned here. Introducing mini games can really break a game for some players, especially when you add a lot of them, and we roll Lucky Dice a lot ! Be careful with mini games and listen carefully to the feedback players will give.
And finally, the question everyone is asking : will there be sex scenes, and if there will, have you started working on them ? I'm asking because I wonder if the huge amount of tenants will not make that task harder and harder, the more there are.
Do you have any kind of interactions planned between tenants ? Right now, it feels like they all live in different houses in different cities. It would be a great idea for difficult achievements. For example You make a scene (any kind of (preferably sexy) event in the MC's apartment or in one of the tenant's apartment) with specific multiple tenants (3 sounds nice) and make it a reward for an achievement : "Unlock specific tenants X, Y and Z (for example Vanessa, Nubia and Sofia), get them to A/B intimacy/obsession (or a rank like Servant or Wife)" The only issue would be selecting tenants, because some players will prefer male tenants, or female tenants or a mix.
I will not talk for all players, but instead of new systems (even if I like systems, it's a management game after all, I'm absolutely not asking for a VN), I'd rather see more interactions with tenants, between tenants, with NPCs or between tenants and NPCs. But again, the large amounts of tenants might make this too difficult. An option would be to have a selection of tenants who would be more fleshed out (interacting with each other, the MC, NPCs) while others would remain more basic.
I find it a little weird that you decided to make the NPCs family members of the MC. Unless you add incest (which I wouldn't mind) it means we will never have a sexual interaction with those really attractive characters.
