1.It's good that you noticed the limitations and if your code doesn't collide with the limitations, then you can switch seamlessly from MySQL to StoneDB.
2.There are always some limiations for a universary DBMS product, like the limitations of MySQL heatwave at https://dev.mysql.com/doc/heatwave/en/heatwave-limitations.h...
3.StoneDB is a new emerging HTAP database.It's natural with some limitations.And these limitations will become fewer and fewer in the nearby future.