Have the ability to set up a subscription with a recurring fee instead of just a one-time fee would be helpful. A workaround is to create a new line item that is recurring, however, this limits one to use a fixed-rate rather than be able to apply a percentage.
Having the flexibility to apply a recurring percentage-based fee to subscriptions would be greatly appreciated!
To add on to MStrange's comment, we pass on our CC and direct debit fees. We do not want to add these as recurring line items because that will affect the MRR calculation. Being able to add a recurring fee or tax rate to the subscription total would be a great addition.