First, I have no idea why he's so small. Part of it is because they set him so far back, presumably to accommodate the apparatuses, but in that case you just make him bigger. Seems weird.
Second, I have no idea why they didn't use better audio footage. We Rock sounded like it was recorded on one of his last tours. Why not use the Spectrum audio, which sounded great?
Third, why not use a holographic (yeah, I know, Pepper's Ghost) Jimmy Bain and Claude Schnell, too? It'd be better if they were presenting it as something other than a rock concert. Like somebody else said, I'd rather just go somewhere and watch the Spectrum show on a big screen with concert loud audio. If it were presented as a better movie with a band of holograms I'd be much cooler with it.
Fourth, if they want to do it tastefully, you treat it as a retrospective with guest singers and only have Holographic Dio on 3 or 4 songs. Do it chronologically and have Dio introduce the various segments with Twentieth Century Greensleeves, Heaven and Hell with the two shapes and all the pyro, Last in Line, and maybe close it out with We Rock. Various other singers do the rest of it.
Fifth, this all began with Wendy. Honestly, I'd trust her to know what he would or would not have approved of. I'm sure it's a cash grab for Goldie and Wright, but Wendy might well be differently motivated.
Sixth, I'll pass.