Sounds like FUD. Care to share some examples? Note, in most cases, the DAL has fewer, not more limitations than a typical ORM. web2py does use standard Python. What bad practices? Have you seen this: http://www.infoworld.com/slideshow/24605/infoworlds-2012-tec...?
Which parts? IMO, the web2py framework is not excellent.
It sounds like you hit some limitations with the DAL and switched away, but those type of limitations are peppered throughout the framework.
Web2py is not well designed, not standard python (look at the source), and it tricks newbies into bad practices.