I see nothing wrong with the plan, assuming you do keep some basics in mind. One is that the tank end of the pipe has to always be in the water so that the siphon is not lost when the tank drains down and two, the ball valve has to be low enough to make the water amount on the outside exceed the amount you need to move up and over the rim. In moving and over the rim to start down. other words make sure the water going down the outside is enough to get the water going up. Also be aware that things like bubbles going up into the pipe will tend to gradually kill the siphon so keep it away from any bubbles, etc.
For a low effort operation, I once had six tanks with a combined drain of this sort but used a solenoid on a timer at the drain in another basement room to open and start flow. Then I had a barrel of reserve water which I treated and let a timer pump it back into the tanks.
One could say changing more water and letting it drive the overflow would do the same except that would also mean part of the new water was draining out, so I opted for the more complex setup.
I was working massive hours at the time and doing water changes seemed a good idea but it also had problems of various sorts losing siphon and overflowing the tanks. I eventually decided I needed more personal time to actually see what the fish were doing more than I needed the cut in time.