Though I guess one can overdo it.
Imagine if you really had all the possible actions, spells, magical items, and whatever else on cards - you end up with one (or several) card decks that you would have to go through too, which would be just as bad as skimming through a rulebook, except that you certainly don't have a table of contents for your "combat maneuver deck".
Though, this of course depends on how many different options (cards) are available for each type of card/deck you're making.
Magical Items: Works well, because each player has only a limited amount of actions.
Combat Maneuvers: Might become a real hassle for a high level Fighter. A table containing all possible options is probably easier.
Spells: High level casters probably would benefit more from ring binder containing their spells (but the things you bind might in fact be cards), possibly organized by level or alphabet or both.
Quests: Good idea, might be also organized in some kind of ring binder or journal for long-running or very free-form campaigns.
The important thing is always to keep the information organized, so you find it quickly. If you memorize the pages for each combat option in the rule book, you don't need cards, and if you have 40 cards, they won't help that you much...