and I only worked all this out last week.

Well damn, I was too late then!

For setting autovotes, do you know which delay works out best, 4 or 5 mins?

I use 4 minutes, but barely ever get in the top curators on @abh12345's weekly posts. I think the people on that chart are 100% auto-voter ones. I do too much manual curation to appear in it.

Curating comments is worthwhile too if you can breach the dust level. This one is your 'post' but as it's 10 hours old and I am the first voter, I will get half of the rewards for the vote I am about to give it.

I read a long time ago that the first 4 votes are the most valuable ones on a post (or a comment) when it comes to curation.

The curation on a comment for me might be peanuts, but it all adds up.