So, played throught the whole thing. Got most of the stuff unlocked - missing one pregnant scene and bunch of rumor scenes. It was mostly just an OCD thing that made me do it. Kinda wanted to "clear" this thing and wasn't really feeling energetic enough to do anything actually constructive with my Friday evening.
Beating the game does take a while, and whether or not it's worth it is... well a matter of taste. The scenes aint half bad, as far as this sortta static style goes, and the "storyline" is... Well it gave me a few chuckles along the way, and is more or less what one would expect from a game like this. I mean, it's pretty dumb and holds not pretense about any sort of realism or believability, and the characters act in utterly ridicilous manner. But that's kinda par for the course for these make girls adore you through the power of rape and drugs.
The most obvious issue, that most people playing this will hit, is the sudden ending and the whole new game+ start from the beginning nonsense. You don't actually have to do that though. Once the condition for a specific ending have been earned, the game will play that particular ending scene. But once it is unlocked, it wont trigger again. So you can just go back to an old save and keep playing. That's what I did, and that's how I ended up with all girls as my maids. Good example of this is Arle - once you get her as a maid, the game will play the Legendary Adventurer King Ending. After watching that just go back to your old game save and continue playing. It wont trigger again once you "get" Arle "again".
As for unlocking the girls - most of them have some condition that has to be met in order for them to start visiting your inn. For example, the minstrel girl will only start visiting once you have explored Secret Cave at least once, and the demon girl is the first end boss of Legendary Labyrinth. You need to finish the final level and beat her before she starts visiting your inn.
So just explore everyplace and clear all levels of the dungeons. Eventually all girls will visit your inn.
As for exploring and combat - it is ridiculously simple and straightforward. I found the most efficient way to deal with that nonsense was with thugs. Thugs are cheap and plentiful and thus benefit most from the girls special powers. The strength buffs and resurrection abilities. So just recruit 1000 or so thugs and you're good to go.
At the start of the game, when you are low on funds, it is more effective to recruit them in lots of 1000 gold. You may get up to 25 per 1000 gold that way, while investing 5000 may just give you 65. At later stages I recruited thugs by dumping 30 to 50 thousand gold in 5k batches. I mean I had over 100k gold at that point and was getting 5k a day at minimum so it really didn't matter much.
I also found that things got lot easier by playing the game to what ever first ending you manage to accomplish and then starting a new game plus with the intention of getting all the girls on that second playthrough. Money is in short supply at the start of the game and will drag things out. On many days you will be just generating gold to keep your inn supplied and your forces strong enough and wont be progressing with any of the girls. By starting a new game with the money and inventory and troops from your first game, you will make the overall thing lot less of a hassle. You can then concentrate on getting the girls instead of managing your inn.
So if your first game ends around day 40 or so, then start a new game. By day 80 of your second playthrough you will have pretty much everything unlocked. If you try to do everything on your first save... Getting to the end may take more like 200 days.
Trying to get Arle on your first play though is tough, getting her on the second one is also tough but doable. This is because you need unicorn horns for her which are a late game item, while Arle start visiting the game around the 30% mark. Having her ASAP will make things lot easier though, since her ability is really useful. Especially when combined with Charon's. Those two will make thugs unstoppable wave of murder. And the 3 healers will resurrect most of your casualties.
It's really unlikely that you will have the necessary horns by the end of your first playthrough (I mean you could always continue it by loading an older save after the ending scene... But starting a new game will make it so much quicker. Trust me, I tried both ways.) To get the horns you need, use your firs play though to build a 1000 thug horde, and then on your new game plus make a beeline to the final dungeon and get Charon ASAP. You need 4 horns total, and wont need them for anything else. Getting them will be a matter of RNG so some save scumming will be helpful here.
And talking about save scumming... The most problematic piece in the whole game is getting enough Sea Snake Blood. They only spawn in the one shot travel battles and in Rumored Labyrinth. You may encounter them as regular monsters there, but there are dozen other monsters that you might also bump into, so encountering them is kinda rare. And their blood is not a guaranteed drop. Your best bet is to keep doing Floor 2 of said dungeon over and over again. The end boss is a Sea Snake so at least that is a guaranteed encounter. It still might not drop the blood so... Save before trying and reload if you fail to get any.
And that's about all there is to it.
