As SW just said earlier, it is not the seat heaters or window actuators that are major issues nor frequent problems, but covering the engine and components, and the transmission that are THE prime issues.
Buying a warranty is like any other insurance policy in my opinion. It is simply a matter of how much expense you are willing to bear on your own, versus paying the onetime fee and I assume, a per occurrence deductible. For me, I look at how much I keep in the "Cookie Jar" for unplanned expenses, or do I want to put a $1,000. or so on a credit card when or if I have to go in to the shop.
I am not sure you asked for it, but given how you described your situation, mu suggestion would be to go ahead with the warranty.
Paul