nVision Vs XMLP - GL Reports Using Trees

  Is there a way that we could use Peoplesoft trees to report on XML Publisher? Well, I have developed few nVision reports that report the Budget Vs Actuals , but if I were to develop using XML Publisher, I am thinking I need to write Application Engines to populate staging tables, write queries out of it and report XMLP, which is going to be a lot of work. The reason being I have to consider Account, Class Field and Fund Code trees on top of the Ledger tables. 

So I am curious if there is an easy way to use trees when developing XMLP reports. Please advise