In addition to Cap the other series I had a subscription to was X-Men.
Uncanny X-Men - Phoenix was dead, had been for about a year, and Uncanny X-Men was definitely the book that everyone reading comic books seemed to be talking about. I am sure that was due in part to the beautiful job John Byrne and Terry Austin were doing illustrating the series. By the time I started collecting Byrne and Austin were gone. Chris Claremont was still writing and Dave Cockrum was back penciling the series.
At first I was disappointed but the quality of the stories soon picked up. The first couple issues weren't great.
#152 - I can't remember what this one was all about. On the cover Storm is fighting Emma Frost. Presumably that also happened in the issue but I can't remember what else.
# 153 - One-shot. Kitty has a dream or tells a story à la 1001 nights. I don't think I was spectacularly impressed by this issue. Not bad but not what I wanted.
# 154 & 155 - This is where it started to get better. Cyclops' father, Corsair, returns from outer space. He is being pursued by aliens. Colossus seemingly gets killed during the fight with the aliens but he back on the cover a few issues later. I can't remember how he is saved but I think it might have been by some of the Corsair's alien buddies, the Starjammers.
# 156 & 157 - More Starjammers plus the Shi'ar. The X-Men leave earth temporarily. Warbird, Lilandra's sister is their primary foe.
# 158 - Rogue is on the cover but from what I gather she was still a villain at this point and it would be more than I year before she would join the team.
# 159 - Dracula attempts to turn Storm into his consort. Of course he was ultimately unsuccesful. I remember this issue because it marked the first time I learned that holy symbols like crosses only could affect Dracula if the bearer believed. Overall a pretty good story from what I recall
# 160 - Colossus' sister Illyana is kidnapped by a demon, Belasco. Magic wasn't exactly what I was hoping to read about in X-Men but I think I enjoyed this issue. Especially cool was how Illyana was only gone for a few moments out of the X-Men's lives but years passed for her and she came back a teenager.
# 161 - Probably my favorite single issue from this run. A one-shot story about the past. Professor X and Magneto team up to fight Baron Stucker.
# 162 & 163 - The X-Men return to outer space and fight the Brood. These two issues are just the beginning of a story that ran through issue 167.
I was hooked at this point. I continued to collect and read Uncanny X-Men for a couple more years. Not sure why I ultimately dropped it. My favorite multi-part story following the Brood story was probably the one featuring the Morlocks. After that the title languished a bit. I've tried a couple times but never been able to get myself to read much following the early 180s. I still enjoy going back to read these stories and hope that one day they will be available in a Marvel Masterworks colleciton.