I have used Data Developments - it can be good for fund accounting. At the time (over 5 years ago), I wasn't doing much else, so one gets used to what one knows. Don't know I can help much now though as it's so long ago. The person who took over from me went back to spreadsheets, so I know not everyone would find it straightforward.
What I would recommend is ACAT - Association of Church Accountants and Treasurers https://www.acat.uk.com/. They may be willing to pass your details on to someone who is using that software regularly and would be willing at least to help you extract the bits you need in order to move it elsewhere.
I've found Xero good enough for fund accounting - using the tracking options, as I still deal with a number of church related charities. I expect Quickbooks has a similar function.
All the best,