I get that you can reload and go a different path for the achievements, but I'd like to end a game where I can help everyone and not leave anyone hanging. it's a weird feeling, but it's satisfying when I do it
Viewing post in Could we get some more spare days between story related events?
Sorry to dash your hopes, but this is unlikely in any build of the game, and will probably never be possible in the final build of the game. The last major update with the least amount of guest content definitely did not have enough days to finish them all. I think that this pattern will continue as they add more side content. And just to inform you, you probably can't help everyone (or exhaust their routes) in one save in the final build because this is a deliberate design choice by the devs. One of the devlogs explains this in detail
The more you know the game and how its systems work, the more you can manage to do in a single run. However, nanoff stated in a Q&A that he disliked how hyper managed the Persona series is to achieve everything in a single play so they've specifically designed it so you can't do that. It's got a different feeling than many VNs that have divergent content as it's usually tied to a route, but here it is only your stats and decisions that affect these.
Specifics (Spoilers)
Managing the danger system and getting Robert ASAP go a long way if you want to up your resources. As of this build, choosing art and grabbing Wolf allows for the most resources to complete projects, however choosing Wolf means you lose out on having both Khenbish and Themba at the drinking game, which is the most fun way to experience that scene.
There's always going to be a compromise and so you can either worry about that or go at your own pace. The lack of satisfaction is also a major theme of the game but told through a mechanic. Time is a constant factor, whether it's through repetition or the knowledge that you're missing something had you made choices that are different. The most satisfying moment was after multiple playthroughs, unlocking meaningful new dialogue in Chapter 18 by playing my part instead of doing what I would normally do instinctually. There's a lot of mystery just under the surface that you may miss by only min-maxing the ideal route.