D7 Visa- Can anybody offer some simple insight into the process?

Hello there! I hope all is well.

I know you guys get asked... a LOT... about the d7 visa. I have read through this forum, gone through google with a fine-toothed comb and yet still can't seem to find any definitive answers 😅

Whilst I understand it's very much treated on a case-by-case basis, I'm just looking to get an overall idea of process and timeline.  If anyone could help me, that would be increds.

My situation: I am a single British female who worked as a European tour leader and was going to apply for my Portuguese residency until Covid hit and I got stuck in the UK meaning the Brexit deadline passed.
I now working as a remote full-time creative copywriter for a London-agency and would like to apply for a D7 visa. I earn substantially over the minimum required passive income, I have a letter from my friend in Portugal (well, the form) stating I will stay with her, a letter from my employer confirming salary and job title, am just about to apply for my NIF and bank account with Bordr and can access docs like criminal record check. I don't have huuuge savings due to being in London for two years (dang those London prices) but my salary is good and constant.

I am looking to move in late January but cannot apply just yet as I am under the impression they keep your passport for a while and I'm in Italy for work for a couple of weeks in October.

I guess my questions are:

1.  Is there anything I am missing or not considering doc-wise?
2. When would be the optimal time to apply as I hear things are taking a little longer due to Covid?
3. Do I apply directly to VFS and have my appointment with them?
4. Is D7 the only visa I'd be able to apply for in my situation? Is it the best one?
5. Is there any other info you think is pertinent?

Thank you SO much in advance for your patient with this manuscript of a post.