For example, does the ring feature allow you to see if power is going through an encircled wire?
Yes,
If you have enough current going through said wire. I wouldn't think you would use it too often in that application, though you could measure your current draw to the starter while under load.
Mo better for wire troubleshooting of grounds and power connections (voltage and resistance/ohms). Handy and useful when you get the knack. Not too steep a learning curve with a little time. Good price for a committed boat tool. Pays for itself after a couple of uses. Works on your vehicle and around the house.
The clamp is more useful in the AC current mode (IMHO) but I did use mine to measure DC current at the starter for cable sizing.