I don't think she's too young to have TV taken away. I think she's too young to be watching very much TV, period.
TV has a deleterious effect on young children's neurological processing. It trains them to expect instant gratification, and it short-circuits their verbal and visual imaginations at the precise developmental point when their minds should be popping with creativity.
When my son was that age, we established a rule that's still in place today. Friday nights are movie night. Aside from that, he gets no visual media whatsoever. His entertainment is, and has always been, reading.
And that (reading to her, I mean) will really help your daughter to focus, to handle disappointment, to think creatively in a calm, reflective way. It's a crucial key to her native intelligence. All the non-TV activities you describe are fantastic, but reading aloud should be front and center.
So, I don't think it's a question of whether you take TV away as a punishment. It's a question of whether and how often TV is an option to begin with.
P.S. Marketing people will have you believe that an iPad is an educational tool. It's not. It may be an efficient way to get her to retain information, but information is not education. It doesn't build the cognitive muscles that are the true heart of education. Instead, it lets them atrophy. Saying it's educational is like saying you can get exercise from driving in a car because your body is in the car and the car is moving. No. To get physical exercise, you need to move your body the hard way. To get mental exercise, you need to move your mind, not have an iPad (or anything else) overload it with excessive visual stimulus. Sorry, mama :(