You could also say, "... was way (too) cool, beyond my expectations."
It's an odd mixture of types of language. "way (too) cool" is very casual and slangy. "Beyond my expectations" is much more formal.
To keep it all in the same style, I would suggest something like:
"...was way (too) cool, (lots) better than I expected."
There is a trick with "way too cool". It can be an insult or a negative evaluation. "Too cool" and "way cool" (which may be more of a California way of saying things) are both usually very complimentary. "Way too cool" can be a judgment that someone or something is over the top. That's my experience, at least.