The controllers were shit, the button pad had these hard to press plastic-y bubble buttons with a touch-tone phone style layout. Laughably bad ergonomics and design, but back then nobody was laughing or even complaining about such matters.
Even though the controller where charitably meh (I disliked the side buttons) The hardest part of playing those games in emulation is getting a controller with a number pad and 16 directions. I tried a couple versions and modern controllers just don’t deal with the keypad well. I have bunch of carriages with the plastic overlays that slide over the number pad that told you what some of the buttons did.
Colecovision has a similar issue.
for football, you entered the play/formation information. Utopia (an island civilization sim) you used it to select what you wanted to build. Math learning games the keypad is self explanatory and for a lot of games it took the place of an on screen menu system(the resolution was low and the fonts quite big)
https://atariage.com/forums/topic/90216-intellivision-overla...
AD&D. Space Battle, and Skiing were my go to games. Night stalker was my brother’s favorite