I am not sure the data you're looking for would really do you any good in determining which certification to go for. There is tons of info on this site alone. Many of the experimental aircraft are easy to fly and some are not, regardless of pilot skill. I think that certified aircraft are the exact same way. The questions you should be asking are:
What is my mission (define your nominal useful load, stall speed, cruise, TOLD, etc)
Determine what certified aircraft would fit the mission
Determine what experimental aircraft would fit the mission
What are your plans for aircraft resale
Then take all the information, throw it out the window and buy the first airplane you see. (all jokes aside your mission and your budget are the factors you must consider) I have, in the past completed prepurchase inspections and recommended to the buyer to walk away. The problem is that the buyer has "Fallen in love" with the aircraft and unless I set him or the aircraft on fire he will disregard my advice and buy it anyway. I am sure other mechs. on the site would agree.
Take your time, decide on an aircraft, go fly one, evaluate your budget, purchase the best one you can find.
And to answer your question. I don't think you will get any useful data from the NTSB or the EAA directly. You may find a way to download the accident database and do your own custom querries on the data versus the standard NTSB search fields. I think you may be able to find some useful data doing it that way but you will need to have some database skills and know what you are looking for.
PM me if you need some help with the database, I'm sure we can get the data you need if we can get that database downloaded.