Hi Dennis. I have to agree with you on the magnitude and location. I would like to make a suggestion you might want to think about.

Let's say you forecast a quake of 7.0 to center at 38.00N/122.00. How large of area will the quake be felt and what would the damage be within that range? If you were within 80Km would you be able to tell the magnitude of that quake based on what you felt and the amount of damage done if the quake was a 6.8Md instead of a 7.0Md? I rather doubt it. The damage could be considerable within 40Km and could be considerably more in a given direction from the epicenter.

This may not be the correct figure, but I think a large quake is considered any quake over 6.7Md and major when it's 8.0Md or larger until you reach 9.0Md. What has to be remembered is that not all quakes last the same amount of time. In many instance the damage from a 6.5Md could be a lot more had the quake lasted another 10 seconds. The Loma Prieta quake lasted 15 seconds. I can tell you this. Had it lasted another 10 seconds the damage in Hollister would have be a lot more then what it was. As the crow flies I live about 20 miles from the epicenter of that quake. My Mother lived about 5 miles from the epicenter. The only thing that happened there was some dishes were broken, and some pictures knocked of some stands.

This is what you proposed.
time frame:
100 points - within window
90 points - within 1 day
80 points - within 3 days
magnitude
100 points - as predicted
90 points - within .2
80 points - within .5
location
100 points - within 25km
90 points - within 50km
80 points - within 100km

The following are my thoughts on any quakes 5.0Md. to 6.5Md. The score is a little more liberal when the quakes are above 6.5Md with the exception of the time frame. It never changes regardless of the magnitude of the quake.

magnitude
100 points - as predicted
90 points - within .5
80 points - within 1.0

location
100 points - within 50km
90 points - within 65km
80 points - within 75km

The time frame is where it gets a little sticky. I think the time frame should be no larger then 5 days. I feel that it would be impractical for a city or an area the size of the Bay Area to evacuate for a period much beyond 5 days.

time frame:
100 points - within a window of 2 days
70 points - within 3 day
50 points - within 5 days

Keep in mind that this is for quakes above 5.0Md.
The above score is for quakes that occur before the forecasted event. The points would drop off considerable if the quake occurs after the forecasted event. Outside the forecasted event is after the window closes.

The scoring system I have imposed on myself is that if the quake occurs after the forecasted event I get a "F" in all categories. To me to have the quake occur after the forecasted event is the same as not forecasting it at all.
I don't use the number system for myself. I use A, B, C, F, for each of the perimeters based on the above limits that I have imposed upon myself.

I also include quakes that I don't forecast. However those are for quakes above 6.0Md.

This is the system I use for myself. It may not be the best, but it does keep me on my toes. Take Care…Don in creepy town.