I'm also a 70s guy, but lately i've been mainly listening to 80s and 90s shows, so i'll pick a few of them.
I love 1990, check out 29/03/90 for a very consistent show with a particularly lovely Bird Song and Eyes of the world.
13/12/80 is great. 1980 as a year is starting to become a favourite of mine. You gotta love those To Lay Me Down's
Dead Set and Reckoning show how great songs from this year could be.
22/06/91 is lovely. Hell in a Bucket, Looks like rain, Terrapin Station. This show lies in the middle of the Bruce Hornsby era so listen for the lovely keyboard riffs
13/07/84 has a very nice dark star
11/10/85 is all nice.
But as for the 60s/70s.
Check out 27/2/69. This is the show that has the magnificent Dark Star from live/dead. Same for St Stephen and The Eleven. The whole show is just perfect, the psychadelic era at its ABSOTELUTE peak. The folliwing night, 28/02/69 is also steller and some say better than the previous, but i'm not sure about that... i need to relisten to them both, but i do know the 28/02/69 dark star, great as it is, lacks the extremely powerful and spooky sense of direction and urgency that the 27/2/69 dark star has, which is exactly what makes it so outstanding. I've never heard another like it, most dark stars are like jams (nothing wrong with that) but it seems to me 27/02/69 is more than that.
Anyway enough about dark stars... they possibly require a thread of their own
This post isn't finished, i'll edit this later to add more of my favourite shows.