I like the system, however I have one problem.
"So, technically, the order in which it was killed does not matter at all, really, but rather how quickly you managed to get the kill."
There MUST be a provision for having killed the previous boss before you can get points on the next one. Otherwise, one can skip to an easy boss and seal the 5000 points while other groups are struggling with the first.
I actually updated yesterday to include all 3 systems so it can be seen side to side - also I aggregated the three (note this could be the actual system too - it is very easy for me to update the spreadsheet after it is coded).
I agree, you must kill in order - that is something that just must be entered manually (visually, it is extremely easy to see if someone went out of order).
thanks for your feedback, I will keep iterating based on feedback and show more systems as examples if needed.