I would not consider 9,000 errors in one day to be normal but I am not a MVP.
On my system every startup/shutdown cycle I have 3 errors and 2 warnings (Errors and Warnings are not the same) and they are the same every time:
Since I've looked into the Errors I know they come from attempts by the system to get a network address when other things on the system are not quite ready yet (since the system is still coming up and not quite "ready"). Then those operations repeat and when things are ready the system succeeds in getting a network address and all is good for the rest of the day - no more errors or warnings for the entire day. The warnings are when the system is shutting down and Services are being stopped. There is probably not much I can do to "fix" those but since I understand what they mean and I don't have any more during the day they do not concern me - I know what they mean.
No event in the Event Viewer log should defy explanation and it could be that some of them could be ignored. I only have 3,673 Administrative Events for the last 7 months (lots and lots and lots of restarts) and you have 9000 a day and don't think it is an indication that something might not be quite right?
I don't see how anybody can say that your events can be ignored without knowing what they are unless one is just in the habit of ignoring events. I would not be able to stand or tolerate 9000 events in one day.
You have learned that unchecking the yellow "File not found" items shown in Autoruns will not make your system run faster. Since they are just references to a path/file/folder on your system that no longer exists there is nothing for them to do so nothing will happen that can consume any time. And you might see them again the next time you restart your system.
The pink/red entries in Autoruns are usually things from third party programs that the publisher did not bother to digitally sign... the Description and Publisher fields are usually empty - probably not a problem.
For startup issues the best place to look in Autoruns is the Logon tab since that is where your startup items are going to be and from there you can methodically uncheck things, restart your system and see how things look:
If your system is just slow starting up and then runs satisfactorily the rest of the time you should look at all of your startup items and the chances are very good that there are many things that can be disabled - at least for testing.
I would be sure to make a System Restore point (to be safe) before you make any permanent changes so in case things get worse, you can undo the changes and start over with your troubleshooting.
Some folks like to use the built in msconfig program to see what their startup items are and then disable the ones they might not need.
Here is what the Startup tab in msconfig looks like on my system:
I don't have any startup items to worry about but you may have some that you need/want and nobody can tell you what you might be able to eliminate without seeing a list.
I'm not a Microsoft MVP but if I had even 9 Administrative Event errors a day I would be tracking them down, coming up with an explanation,figuring out what they mean and making an effort to fix them if I could.
I would not consider 9000, tens of thousands or millions of errors a day in any way to be normal.