Site-wide bp sign up/ register! Right now the most annoying thing with BuddyPress is the broken redirect to the bp register from blogs across the site. If you want comments to only be available to users who are logged in (hopefully to allow more sign ups) you get a set of php errors. In addition you are linked back to a broken sign up page that will allow anyone to circumvent all of your required profile questions and even captcha. This loophole really needs to be fixed site-wide. The only way around it right now is to either fully open comments or close them.
If there is something that will let this bp register work across all the blogs on a bp install that would be awesome!