Sandlot- you make great arguement about the ratio of price to feature.. And I agree...
The taurus, may not be, the most well build vehicle on the road, but truth be told, every vehicle on the road these days, is almost, designed, to be replaced, not repared.. I mean.. look at the situation, we have new versions of exisisting cars coming out every 3 years, new models coming out constantly. Litterally, an overwhelming number of designs... resulting in everything being expensive, and difficult to work on.... Even the expensive toyotas and hondas, will have their problems....
Like you said, you were able to pick up a very new(used) fully featured taurus, for 14k... far less than a comparable offering from the major import options... the amount you saved on inical cost, will more than makup for any differences in repairs or vehicle life that the import option may have had to offer...
These tauruses, really are, a bang-for-buck option.. I have a neighbor who owns 3 of them... all late 90s.. bought them all around 60k miles, for less than $3000.... so he has 3 cars, that his family shares, all relativally "young"... for less than $10k.
The taurus body, is also very "sleek".... they tend to be suprisingly fuel efficiant, even with a decent amount of power under the hood from a V6. (previously mentioned neighbor, routinally gets over 30mpg on the HWY in his V6 taurus wagon)
Back on topic....
I suggest using Motorcraft 5w20 blend, at the interval required to meet the warrenty, that way you aren't met with any hastles if something does crop up.
When the warrenty gives out... do an arx clean and rinse phase on a standard dino (5w20 or 5w30)(penz/gtx/quaker/supertech/mobil5000/exonsuperflo/etc etc etc)... Then switch to a Full synthetic... and work your way up on drain intervals using some oil analysis to determin how long you can go. Since you drive an incredable amount, you won't have time to wait for results to see if you can continue using the oil in the crankcase, the turnaround time on mailing/testing/interpretation is too long... I suggest Blackstone/Dyson (Terry does oil analysis using blackstone labs as the test facility), inform Terry of your situation... send in samples at drain time, and keep extending them based on Terry's interpretation... I don't doubt, he'll recomend LC to extend your oil life... which, in your case, would certainly be benificial.
I wouldn't be suprised, if you could start doing 15-20k mile oil change intervals, or more, usng a top notch oil, like Mobil EP, or redline, with LC added as directed. That way, you won't be under the car changing fluids every other week. The "weak" point of "thin" oils like 5w20, is barrier lubrication- the possability, that the oil film, could break down, and lead to fast met-to-metal wear... a synthetic, regardless of weight, is going to have a much higher film strength, even in 5w20.... A 5w30 wouldn't hurt anything, if you are sceptical of the 5w20 hype.
At the warrenty experation- would also be a good time to arx the transmission/power steering. (maybe someone else could chime in on this- did ford fix the power steering issues? the pumps were super noisey and went out every 30-50k for awhile there)
Your driving style, gets a lot of miles, in short time. Primarily highway, very easy on the oil for the most part.... Just keep the rest of the components working, and you'll be fine... keep doing occasional oil analysis to watch for coolant...
good luck, take it easy.