Okay, voice of experience speaking...I will purposely omit the original, single coil 51- early 57 (and 68-71 Telecasters), as they are unique in sound and playability. 57-mid 65, Fender was winding their pickups by 'hand', which means that someone had to guide the wire onto the bobbin, creating what is referred to as 'scatter-wound' pickups. These are the Golden Years of Fender, and also coincide with the sale to CBS. After mid 65, pickup wire was mechanically fed, creating even tension, and minimizing the possibility of breakage during the winding process. Later 65 and 66 had the same quality as the earlier years.
1967 is when the wheels fell off at Fender, beginning with the resignation of key quality control managers, in particular, Forrest White. CBS brass in NYC didn't understand why Fender paid so much extra for seasoned, dried maple, and to save money, started ordering hundreds of board feet of 'green' maple for necks. How did that go? How many 1967 Fender ANYTHING do you see? Necks warped before they even left the factory...
By early 68, all of the green maple had been removed from production (after a disastrous 1967!), CBS buyers bought the most seasoned maple they could find, and from 68 to 75, things were going fine. In 1976, Fender ramped up production dramatically, and the result was basses with some quality issues- huge gaps in neck pockets, crazy heavy - I owned a 77 Jazz that weighed over 12 pounds-, and the gloppy 'Thick Skin' finishes, which, legend had it, that added a pound to the overall weight. This mass production chaos brought the hit/ miss ratio down to 50/50...yep, there were some good late '70s built, but there were a lot of grossly heavy, poor quality dogs. Anything from mid 76 to 81, approach on a case by case basis.
From 82 to the end of the Fullerton era in 84 saw another shakeup for the better, the vintage reissues, the Elites (first run), and even the US standards were better. From 84 to late 89, there were no US built basses, other than the Vintage Re-issues. 89 to 94 saw the Plus series, very well built and quite under-rated, although not 'traditional'. Beginning in 1995, Fender started doing things right in the traditional sense, and by 1997, you had to look VERY hard to find a bad Fender. What Fender has been doing from late 2007 to the present with quality control, materials and workmanship is unbelievable. So, to sum up...
57-66 pre-CBS / early CBS - golden
68-75 - solid workhorses
76-81 - rolling the dice, but there are some very good ones
82-84 - much better quality control
89-94 - not traditional, but very well built
95-96 - Daddy's Home!
97-07 - Excellent
07 - present - Excellent plus 1
A previous post said to get a new American Standard and try different vintage-voiced pickups. I agree, especially if you don't have the bucks to get into the vintage market.