Duo,
This is not a software issue, but a user issue. You do not yet know how to use the new lights so you should not judge them just yet. Bryce 7 renders much faster than Bryce 6.1 in direct tests. Further, you must be very careful when you compare the render speed of a single point radial to that of a 3d fill, because a 3d fill is made up of several point perspectives, like a group of radials not a single one so they take more time to render. And when it comes it IBL, the illumination is correct. I would say that you have been far too hasty in judging Bryce 7. Once you master all of the new tweaking options, you can get much faster renders.

There are about a dozen new lighting tools, no possible way you have had time to explore what they all do or find the best way of using them. The official documentation is due out soon. You can always ask me to help you use the new lights more efficiently since I wrote the specs for all of these new fetures. You need to work in a new way to take advantage of Bryce 7 the old ways of bryce 6 will not help you much.

Best of luck, and again, I am here to help you with the new lighting, you should take advantage of me.