I tend to agree with the keep it simple philosophy. Unless we really need these event things (and I don't think we do), it would probably add confusion, especially because events are typically nondeterministic, which is generally confusing enough, but making events that are entirely deterministic would probably be worse, because it goes against the norm.
Also, the more data types that are added, the more difficult it may be for a beginner to grasp the limited nature of AGI. They have to learn, "the sum total of all logics and rooms must not exceed 256" and "The sum total of all vars, pics, temporary variables, and timers must not exceed 256."
The main thing I'd say goes against the idea of event syntax is basically that if statements are practically identical (and in fact are identical if we just treat them as macros). If the preprocessor is good enough, anyone who wanted to do things like that could define a macro themselves:
#define OnNewRoom if (new_room)
or
#define OnTimer(val) if (vTimer == (val))
But I don't think it should necessarily be forced on beginners. It's important to make sure that, in defining this new syntax, that it is actually easier for beginners to understand than the (as eidolon said) already pretty straightforward syntax of AGI. The biggest failure of AGI syntax as it is right now I think is the awkwardness of certain structures such as if else if's
if ()
{
}
else
{
if ()
{
}
}
and the lack of easier-to-write structures such as switches.