I hear ya'! It was the 1965 Topps and Philadelphia football issues that got me into the hobby.
After I posted my reply a few days ago, I wanted to mention some small but great looking Topps insert sets from late 60s and early 70s football. They are really great looking sets, loaded with Hall of Famers and quite inexpensive in price. Here are a few examples with the number of cards in parentheseis.
1968 Topps posters (16)
1968 Topps Stand Ups (22)
1970 Topps Glossy ((33)
1970 Topps Posters (24)
1971 Topps Game Inserts (53) this one has a Bradshaw Rookie year card in it!
1971 Topps Posters (32)
These sets are historically very overlooked by the collecting community which has kept their values low over the decades. The same holds true for many of their Topps baseball counterparts. I don't know what it books for now but the 1966 Topps Mantle poster high booked for $20 for decades!!! I hope it has gone up in the last few years because some of these inserts are criminally undervalued.
Have fun with whatever set(s) you try to put together!