I remember playing some of Agnostos' games. He started out like me, by taking inspiration from NTRPG. Except he took so much inspiration that he ended up selling an almost identical game to NTRPG1, so much so that Hanataka (NTRPG's dev) had to ask DLSite to remove the game, which they refused. Kind of a dick move from Agnostos.
I then played another game, his second game, D. P., which meant playing the game once without seeing anything, then having to replay everything once again but this time with the Omniscient PoV on to actually see the scenes. Not the best design imo. And the ending was... kind of average. The main girl went from swearing she'd never forsake her brother to, literally in the next scene after a quick time skip, saying she didn't care about him.
As for Nettle Tribe (or was it Nettle Pain?), I played the early version, but there were combat encounters every 2 steps, so I gave up. That was a few years ago, so it's high likely he's improved the game since then.
You can already play part.2, I'm not sure if you knew?^^ It's been out for a while on here, Patreon, and Steam. It won't be as long as part.1, at most half the length with all the endings. The choices carry over, but you have to use a password you can get at the end of part.1 from the reminiscence room. Otherwise, you can set them to 100% NTR, Revenge, or Happy. There's also a new mechanic that has Leto reacting differently to certain events based on whether you have more NTR, Revenge, or Happy points. It only happens sparsely and isn't extremely developed, but at least that's something new.
I'm not 100% sure how all the endings will be, but I think a freeroam section would fit the NTR endings well and maybe the Revenge ending too. I can't 100% promise there'll be one though, but if I can do it, I will.