Very nice work Jefferson. Glad to see the lens flare feature used so effectively!!

Duo, I see what you are saying to some degree. But IBL is a perfect example of a feature you state repeatedly as broken that is probably not broken. I am in contact with the IBL master Horo, he literally wrote all of the specs for IBL in Bryce and has tested it to be certain it is consistent. Most likely, there is an error in your use of the IBl feature itself. If you are interested in making it work, please share your thoughts on exactly what you find to be broken so I can explain why it is not broken, and if it is, I can explain how to get around it.

Bryce IBL is not perfect, which is one of the reasons the Domes were introduced. The virtual point implementation sucks,  better way would have been to include IBL into an already established full GI skylight system, this way there are no quality issues to deal with. But Bryce has no full GI skylight system so virtual points was the only way.

What I know is wrong as follows: I once used a uniform white hdr image with 0 dynamic range (or directional bias) to test if the resulting illumination striking a cube would be even on all sides, and I found that IBl failed that test, some faces of the cube at world center received 15% more light than others. This has me convinced that all IBL scenes are wrong to some minor degree, but when using hdri with higher dynamic ranges, the problems are less obvious than with a uniform hdr image. There is a bug report filed on that fyi. Domes by comparison pass the cube test in most situations because they are generally unbiased. That is why I introduced them in the first place.

You say very very slow. Double "verys" is a bit much. I think you just used too high of a quality setting for your lights, or maybe you just used too many lights in general. You said you used 5 3D Fills in this one scene, and each has a minimum quality of 24 or 27, so your render has literally 125 or so virtual radials in it. That is why it took so long to render! The new lights themselves render at the speed they should considering what they are. On speed, the sad truth, is that slower computers do not provide as much return as faster ones when it comes to advanced looking scenes in Bryce.