What to do when super rich?

Its 1420 and im Venice. Early expansion making vassals thru wars brought me 1444 eu4 Venice borders but by 1360 in my current run. I been slowly eating away at northern Italy and even have all of the creation lands from my own borders down to regusa fully integrated and cored. Working on munching thru Serbia.

Im getting bored tho. I have over 20k denars with 300 monthly denars and i got a very advance army for my time period. Almost 3k regulars in just 1420.

What do I do now? Im rich. Strong. And a kingdom.