This thread is really just going to be a lot of personal opinions. But on a similar note to the Oliver 550 mentioned above, the slightly earlier Cockshutts - 540, 550, 560 (the real Cockshutts and not the later rebadged Oliver 550) were also superb tractors - especially considering what else was available in that era (late 50's - I realize a little earlier than you're talking about). Fully independent PTO, finger-tip power steering (though had to be ordered as a option on some of the earliest ones), superb operator access and great layout. Common, dead-simple, and bulletproof Continental, Perkins, or Hercules engines (depending on the model), great gear patterns and speed selection, great three-point with fully independent hydraulics and draft control, built nice and heavy where they need to be, but still nimble tractors. Really just a sensible, comfortable, bulletproof, modern tractor.
Whenever I use our little 540 I think that, if I wanted to buy a new utility tractor today to use for the same purposes, I don't think I'd want a single thing different. Although I do like the IHs, Deeres, Allis's, etc, of the same era for nostalgic reasons, I do sometimes wonder why anyone would have chosen one of them over the Cockshutts. Cockshutt had a modern comfortable and sensible layout, a side-access operator position, modern independent PTO and great hydraulics, etc, while some other manufacturers were still making some tall, gangly tractors you crawled on from the rear, had you sitting like you were giving birth, geared PTO or hydraulics (or at best a dual stage clutch), goofy and knee-cracking shift patterns, no (or lousy) power steering, lower pressure and low-flow hydraulics, gauge and controls you had to practically use a broom handle to reach or have a pair of binoculars to see, etc.
But, getting back to your original question and if you are only looking at 70's tractors, I'd tend to agree with RRlund about those Deere's (though stay well away from the 1010 and 2010). But I'd also throw in some of the Ford thousand series as well.
