Ok to stop 10 yrs of crestor (rosuvastatin) 5mg and baby aspirin (preventive due family history) and go vegan? Health is excellent.

No it's NOT okay. Be thankful for good health. And please be aware that while vegans have the moral high ground, most of the health benefits claimed for the diet disappear when one controls for the the fact that vegans tend to have other healthy lifestyle factors. "The China Study" never resulted in a real scientific publication, and you'd be making a bad mistake to assime veganism will protect your arteries.
OK to stop. Calculate cardiac risk. Use framingham risk calculator on-line. Consider how many years you have left to live and see if calculator numbers make sense to you. Then go vegan and see if you can change your ldl. You might be surprised at how little control you have over genetics. Recalculate your risk. Both asa and statins are weak for primary prevention in healthy people.
Work with Dr. I applaud your decision to eat nutritiously! It is best to work with your doctor to start decreasing your cholesterol medication slowly, while checking lab values periodically to make sure you don't need the medication anymore. Baby Aspirin can still be a good idea to maintain vascular health and prevent blood clots. I encourage you to work with your doctor to make these changes!
Go vegan first. The answer depends on the specifics of your story. Was your cholesterol high? Have you had a special lipoprotein analysis done (such a s vap, berkeley, or spectracell lpp)? Without knowing more, my suggestion would be to have a lipoprotein analysis done, go vegan, repeat the lipoprotein test, then wean off your meds.