Improved Close Book
I'd like to have a better "Close Book" implementation. This should be implemented without affecting the reports (meaning, that the zeroing transactions would never be included in the reports). I'd like to be able to produce reports over several years.
Probably the easiest option would be to add a "purge" feature that removes all entries before a requested date and enter a "Starting Balance" entry to compensate. This would allow for removal of old data that is no longer needed helping to keep the file size down. With that I would suggest a warning to backup/copy file before purging is done.
My preferred option, but probably a little tougher, would be to have an archive feature that copies (or exports) the entries before user selected date to an archive file and then removes them. Adding the adjusted "Starting Balance" entry of course.
For budgeting to work, there really needs to be a way to mark a transaction as a "roll-up" transaction so that it can be filtered out when creating reports.
The common "hack" of doing roll-up on January 1st is just that, a hack.
Ian K commented
I'd like to be able to remove transactions before a certain date, replacing them with a single 'brought forward' or 'opening balance' transaction. This would preserve the balance sheet totals whilst removing old transactions, making the database smaller.