HDRI Capture Methodology

[FLP]

We recently acquired a RICOH THETA Z1 and natural I am looking to create our own exterior HDRI's. It would be nice to have building reflections match the specific site rather than using PS tricks and overlays.

I have shot a few environments already and am looking for some feed back on my Methodology. I have chosen to test my created HDRI against a PG created one that I have been using forever (1433 Sun Blue Sky).

A; The Z1 was pointed so the sun was directly centered on the front lens.
B: The X-Rite Color Checker Classic was centered on the rear lens, perpendicular to the ground, illuminated by the sun.
C: Manual (shutter speed change only) exposures @ -4EV, -2EV, 0EV, +2EV, +4EV saved as a DNG
D: Color profile created with X-Rite Color Checker Camera Calibration tool from 0EV DNG
E: Profile applied to DNG in lightroom. Only edits to noise and sharpening.
F: Stitched with RICOH LR tool. (the tool converts the DNG with edits to a 16bit TIFF in sRGB color space)
G: Stiched TIFF's loaded in Photoshop's HDR Pro tool, merged with no ghost removal and no additional tone mapping in CamRAW.
H: Additional 5EV disk added to sun area.
I: Saved as 32bit HDR

Any thoughts or pointers?

[^Lele^]

Well, does it light a 0.6f gray diffuse plane the same way a gray from a passport looks in the shot images?
Then you'd know if the HDR matches also for light flux, instead of just as reflection probe.
I happen to have made a script to create said passport in max, with v-ray diffuse materials of the correct colors.
Grab the latest version if you want, but use it at your own risk!