Nice thought Sythen. I was also thinking something similar in approach but different in sense of its implication like - It would be nice if we can see the Photon Gathering/Importance Sampling while Light Build (Like Vray Irradiance Samples or any other common renderer out in the market), that will give tremendous visual information for actual working of Lightmass and will eventually help in understanding and manipulating settings in Baselightmass somewhat easy. 4.11 is far more better then any previous Engine versions but still I feel like it lack basic tools for refining or finding bugs while light building, especially when it comes to tweaking Lightmass settings (Lightmass settings available in Engine UI are painfully simple). As I have reiterated many times before that simple settings of Lightmass are perfect for quick setup but may become major hindrance when it comes to adjusting or manipulating it for realistic light build, Ultimately there is no other option but to jump in BaseLightmass for Final Built. Portals made a major impact for small scenes now, simply putting it solves 90% of the bugs but for complex scenes we still require some kind of editing in BaseLightmass to get that super clean look.
It would be nice if we can see some more features in Engine UI itself regarding Lightmass, More detailed settings related to Photon Density, Irradiance Samples, Irradiance Radius and so on with ample explanations in Engine Docs for Noobs like me and not only for hardcore programmers out there (I think Engine Help Documents need serious update regarding the Lightmass Settings and Portal help).
Lighting Quality presets are really helpful but If we can get something similar for Lightmass settings also like - Expert Mode or Advanced Mode - Giving users enough settings to fully control the behavior and intricacies involved.
Here’s the thing you shouldn’t have to get that deep into tweaking to get good results! The render engine needs to be easier to use not harder, I’m no expert but I have used many engines and this is the most difficult to get right. In the real world of paying jobs in Architecture you don’t usually have days to tweak lightmass settings, for video game makers it’s different those are usually long term projects. I don’t know why we don’t have something like “samples” which seems to be standard nomenclature for render engines - e.g. turn up the samples and get better quality (longer render times too!).