"so much going on" is a correct and usable phrase in written English. You can use it to describe a situation that has a lot of activity or involvements, such as: "There's so much going on in the city right now - the protest, the parade, and the carnival all in one day!".
so much going on.
"There is so much going on now.
There was so much going on behind her eyes".
With so much going on, the food can get lost.
I've got so much going on at the moment".
It has so much going on, it's positively operatic.
There's just so much going on out there.
There was so much going on, police and press.
"There's so much going on out there," he sighed.
"Right now, there is so much going on," Schleper said.
And there's so much going on in it.
Being a terminologist, I care about word choice. Ludwig simply helps me pick the best words for any translation. Five stars!
Maria Pia Montoro
Terminologist and Q/A Analyst @ Translation Centre for the Bodies of the European Union