Were people using it as an actual ES replacement for logs? fluentd -> GCP log sink -> BQ can get awful if you need to work with it on daily basis

Curious how was it awful for you? Really have not regretted any part of using BigQuery.

is kinesis in the middle for more durability/being able to handle spikes? when and how does one make that sort of decision to insert kinesis into things? (esp since you were gonna get the data from aws -> gcp so you dont save anything staying within aws anyway)