email template by customer settings
allow a setting to assign an email template by customer for the invoice and future invoices
so that if customer A is always autopay - I can set that email template up to always be the default and this would save a TON of time by not having to individually select the email template each month.
Then for subscriptions, I could batch choose all the clients I want to send invoices to and since the email default is set at the customer level, it would create a huge time savings and efficiency.