The only reason for this discrepancy I can agree with is if the network weight for the total number of coins is incorrect. Looking forward to the reply from the Blackcoin devs on this one.
Of course, I hope your numbers are a good representation of what to expect in V8. Those investments (while still too high for many new miners) are manageable.
I agree that they are too high and that we should come up with alternative ways of paying the researchers. Luckily several options are in the pipe :)