Just as in all navigation, the key isn't really the amount of options/actions but how understandable they are and how they fit to user's mental model of the application in use and its purpose.
As a rule, you need enough categories to adequately represent the scope of information offered on your site or application.
Top 3 IA Questions about Navigation Menus
Google Material Design could be considered as a good guideline on cards.
The primary action in a card is typically the card itself.
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Limit supplemental actions to two actions, in addition to an overflow menu.
If we take Etsy as an example, they seem to follow these guidelines. On the frontpage, Trending Items cards have one primary action and two supplemental actions.
Red is the primary action, the trending item. Green is supplemental action for browsing other similar (trending?) items. Blue is another supplemental action, link to the seller of the item in the primary action area.
I first thought items on supplemental action area marked in green were from the same seller as the item in the primary action area. So the green supplemental action was understandable (more items) but didn't quite fit my mental model (who is the seller).
Cards in the category pages aren't more complex either. They too have one primary action and two supplemental actions.
Primary action area is again marked in red, link to the item. I haven't registered with Etsy so I might go wrong on the supplemental action marked in green. That only shows if my mental model is compatible with designer's intentions.
Though there are two buttons, they are considered as the same kind of actions and therefore are grouped as one supplemental action, add to favourites or add to (wish)list.
Second supplemental action is a link to seller, marked in blue.
Though Google suggests one primary action with two supplemental actions and Etsy implements them, there is an example on Material design with four action areas. It all comes down to how meaningful and understandable the actions are.
