I'd still use the three finger drag. I couldn't give it up since it became an option with my 2008 MacBook.
You can still use two fingers and press with one while dragging with the other, typically pressing with your thumb and dragging with your index/middle finger.
The option to turn it on in El Capitan is the same as with the new force touch trackpad equipped Macs. It's under Accessibility - Mouse & Trackpad.