Imagine the rainbow of tinted smoke from full Angel's petrochem. Can't wait.

Mall/utility or anything that isn't in constant high demand:

For vanilla it's usually passive provider, with recycling done with a requester set by circuit condition (central green circuit web across entire mall for "needed" amount + arithmetic combinator to filter out only required signal for that ...

On 3 different playthroughs now, depending on what I feel like working on at a time.

1) Seablock - long term goal is to just finish, short term as of now is to make what I have now (just got blue science automated) working without breaking due to byproduct overstock before I go towards next steps ...

https://github.com/wube/factorio-data have all up-to-date prototypes including recipes, production speed for different structures etc. - and starting from that you should be able to calculate all other things by hand (for possibly missing info like inserter/belt speed there are exact values on wiki ...