You can separate strategies in one single account by tagging your orders via the api. The tags are returned with executions/fills.
Same here. I do not have an FA account but a regular account. In this account I have multiple accounts (Uxxx numbers). These all share the same market data subscriptions. I don’t pay for each Uxxx account separately.
The reason why I have multiple Uxxx accounts is to be able to separate strategies.