Adding content to IPFS is quite slow...Any ideas on why and how to speed things up?

The current default datastore is slow for small writes. I recommend trying the badger datastore. You can configure it on init by running ipfs init --profile=badgerds.

This datastore should become the default in the near future once https://github.com/ipfs/go-ds-badger/issues/86 and https://github.com/ipfs/go-ds-badger/issues/54 are fixed.