Glad you feel better, just trying to walk with you down a well-trodden path as best as I can
Well fixing the first nap is something I've had to do with both of mine, to fit in with school drop off, either my own or DS's CM when he was young. But I've loved having that consistency, so much easier to tweak fewer variables in the day
And whilst we've still had our fair share of EWs and wonky naps, I think the approach has worked fairly well I'm general. Looking at the examples you've given, I'd say aim for the first nap between 9-9.30, try picking a time and sticking to it, see what happens. I personally prefer to go for 3h after 'up' time (as opposed to awake time, which obviously can vary), some go for up to 3.5h. I like shorter because they're a little less tired so perhaps can cope with the capping better; others find their LOs just can't settle after such a short A time, especially on days when they didn't wake early. Or they find they need to push the morning nap later to combat persistent EWs. Maybe try 9am to start with and push later if you need to? You know your LO best! But I'd personally recommend not going any earlier than the time you've decided, however early she wakes, and religiously cap that nap to the time you've decided - I always regret letting her sleep longer for that morning nap to 'catch up', you want her to catch up in her afternoon nap instead so you can start pushing BT out, if that makes sense? I suspect you may need to go shorter than 30mins but let's see what happens - I'm chicken so tend to go for 5min increments
I'm afraid I'm not an expert on wiwo, have used it but DD has been easier in general than DS, and my memories of those days with him are blissfully blurred
I've certainly used it when OT, can take longer but I don't think it's contraindicated?
Sorry for my rambly tiredness, hope some of that makes sense!