ADF on capital is expensive, and I want it so I do not need to haul two more tugs (and possibly a tanker for extra fuel due to two tugs and extra tanker slurping about as much fuel as a capital) in my fleet. Since it is probably the most expensive hullmod I pay for, and probably one that I will leave on the ship at all times, it makes sense to permamod it so I have more OP for combat stuff, instead of permamodding combat stuff and paying more OP for Augmented Drive Field that I will probably leave on the ship, and have less OP for the other combat stuff I want.
If babysitting remains as insane as it is now, I will settle for nothing less than burn 20, and I do not want a bunch of tugs to do it, especially if I do not have Navigation.
I guess I can care less about burn speed if I plan on total core kill by any means necessary and befriend pirates to eliminate all babysitting. Then again, the Pather bug will be fixed, so player may need to babysit if he wants to alpha spam colonies.