I recommend checking the Changelog in the OP, it explains all the content there is and how to access it.
Events are friday and sunday in the 2 locations, it's a button that appears at the top of the screen.
Investments are income-based only at the moment.
Affinity content will show when you check the different "ACT" options on each of the girls. If nothing happens when you click the different options, they just don't have content (yet). So there's no point in grinding out affinities on everyone.
The dream would obviously be to have 4 paths for every girl, but that would be an insane amount of content if they're all as fleshed out as the current 2, so each girl will probably have a preference path. But here's hoping
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(especially for Condemnation and devotion paths, personally. I just want more toilet content cause I'm a freak like that lol)
At the moment I think there's only 2 paths: Isla's Intimacy and Astrid Bondage, with 6 options each, depending on your respective affinity level.
But affinity is also linked to Wynn and Amaya, Condemnation will unlock small scenes for them. (which the game thankfully tells you, and I hope it remains that way. Content that's too hidden or obscure to access, especially with an expansive system like this, would be obscure and annoying to find)