You can never set too many intentions. Even speaking your intentions aloud 100+ times per day, updating them moment by moment as you go, isn’t too much.
It’s very likely that you’re under-intending. I’d say a good minimum is to set at least 5 fresh intentions every day, and that really just gets you in the door.
Once you get enough practice, it should take you just a few seconds to set an intention. It’s as simple as asking, “What do I want for dinner?” But do this for every part of your day too, such as by asking, “What kind of experience do I want to have while performing this next task?” Then just speak your answer aloud.
When I go running, I clarify what kind of run I want to have. When I start my workday, I set an intention for the type of workday I want to have. Then I update my intention many times throughout the day. This is pretty automatic for me now.