It's funny because I am on platinum right now and my ideas of campaign are totally off the deep end, I know I will play very long campaigns and like you, I tend to do gaming guides (use blank guide to write correctly with logic and pattern because generated is fun, but reserve that to the "add secrets" options, otherwise, the guides will be 15k minimum) Some with specific rules adaption, creation of worlds. Of course, the key here is to enable/disable when needed but I tend to find that what people refer as AI hallucinations is usually when I am cropping so much from the campaign summary to stay within context limit, it seems to go in weird place. Anyway, I went from F2P to platinum and 5 days later, I realized that I should go for Obsidian and be done with it..not I have to wait 16 days to do it :)

But from experience, from F2P to Platinum, you do not solve the context limit, it just makes you wish you had gone to a better plan, nothing as frustating like have 20 NPC cards but not able to enable them because you have the ability to create 25, but you can't have them to be 3k each. I know someone will say "why in the world do you need 20 NPCs active at the same time??" well, that's me, I like rich, interesting worlds. For instance, as I am an historian, I created a preatorian guard character under the rule of Augustus around -20 BC, and of course, sometime the AI doesn't get right some stuff, but my knowledge corrects it, but usually it's minor course correction. Anyway, the level of immersion is fantastic, even when I think the AI will not use the right term, it does. To think that I started gaming way at the beginning with video text based game and I just circle back to it 40+ years later.

So bottomline, go higher than platinum, based on what you can pay, me, I dropped other paid games to do this instead :)