Plantar fasciitis is a degenerative (not inflammatory) repetitive stress injury (RSI). Studies using radioactive tracers have shown that the rate of tissue replacement in connective tissues is often extremely slow, maybe even zero. Therefore these injuries can be extremely slow to heal, and in some cases the microscopic damage is simply permanent. So you really want to avoid injuring these tissues in the first place, and the basic prevention is not to do too high a level of activity.
Although people usually feel PF as heel pain, the damage is actually in the webbing that makes up the arch of the foot, which only happens to have a point of attachment at the heel. You just don't have nerve endings in the main body of the plantar fascia. Therefore the issue isn't really heel strikes or lack of padding in the heels of your shoes. It's just an over-use injury involving the natural use of the whole foot. Plantar fasciitis is correlated with obesity and with standing up while working, but that's probably not so relevant here.
There are many treatments that have been promoted for PF, but the scientific evidence for almost all of them is weak. There is no evidence to support massage, stretching, taping, therapeutic ultrasound, or modifying the patient's stride.
Orthotics are the one treatment that is reasonably well supported by research. Custom orthotics are no better than cheap off-the-shelf ones. The idea that they correct problems with mechanical alignment is empirically false. Many podiatrists believe that choosing the right orthotic is important, and that they know how to do it; evidence doesn't support this. Orthotics provide an improvement in function that lasts for a few months. They do not give any statistically significant reduction of pain. After 12 months, they're no better than a sham treatment consisting of an orthotic made of soft, thin foam.
Sources:
Injury Series: Plantar fasciitis in runners as a degenerative overuse injury
Treat Me, but No Tricks Please
Close Look at Orthotics Raises a Welter of Doubts
Effect of Shoe Inserts on Kinematics, Center of Pressure, and Leg Joint Moments during Running