I didn't see anything in the documentation, so asking here.
Can JoomDonation be set up to automatically send customizable pdf donation receipts similar to some of your other extensions? I am hoping that donations made by credit card would be automatically sent and ones with pay later (cash or cheque) sent once they are marked as paid.
Yes, Joom Donation supports Donation receipt feature, you can setup content of Receipt through Joom Donation Configuration page -> Tab: Invoice Setting.
The Receipt will be sent to donors once they complete the online payment.