it depends on how those events are structured and what they are doing...
having thousands of events can work just fine, but you should use the debugger to see how it is running (cpu usage, memory, fps).
Having that many global variables sounds like it would be very difficult to manage... there are probably much more efficient ways to store the data you need by using instance variables, arrays, and other techniques. If you describe what your goals are, we can make more specific suggestions.