features
 register
  description matching
  regexp matching

 balance
  show top-level acct balances
  show all account balances

 print
 more directives, eg include
 read timelog files
 -p period expressions
 -d display expressions
 -j and -J graph data output
 graph automation
 auto entry generation
 read gnucash files

testing
 ledger regression/compatibility tests

environment
 cleaner option processing
 robust ledger file finding

documentation
 literate docs
 haddock

marketing
 set up as a cabal/hackage project following wiki howto ?
 announce on haskell list, wiki