I'm not a Kafka expert. Last time I've checked, Kafka still misses some important features to be able to fully support this architecture, in particular:

1) Delayed messages

2) Queues

Delayed messages are used to manage time within business processes (e.g. starting a task next Monday at 9am). Queues are used to scale Service workers.

AFAIK queues are coming with KIP-932. I do not know about delayed messages.

Once those features are available, it should be quite easy to support Kafka, probably less than 2 months of work, for a first working prototype.