Critique my St. Louis vacation itinerary!

Hello St. Louisans! I'm planning a family trip to your city in early April. We'll be travelling with 3 boys ages 8, 10, and 12. It will be our first time in St. Louis, and I've been spending a lot of time on the Internet searching for things to do that will keep the kids (and their parents) entertained. I would love your comments and suggestions.

Here's our plan so far:

Day 1 (Wednesday)We'll probably arrive in the late afternoon. We'll be staying in an AirBnB just south of Tower Grove Park. After we settle in, I'm thinking that we'll head to the Delmar Loop for dinner at Salt + Smoke, then walk over to Magic Mini Golf.

Day 2 (Thursday)This is the day for the City Muesum. I'm planning to get there when they open, and let the boys run around until they drop. Afterwards, we'll head to The Fountain on Locust for some food and/or ice cream. If they have any energy left, we'll check out the Walls Off Washington.

Day 3 (Friday)Gateway Arch in the morning (with the tram ride to the top, of course), then walk to the Citygarden Sculpture Park. Depending on our mood, we may visit the Economy Museum as well. Any recommendations for parking near the arch? A lot of the online reviews for the nearby parking garages mention that they only fit compact cars - we'll be driving a minivan.

Next, we'll head to Lafayette Park. We'll visit Park Avenue Coffee to try some gooey butter cake, then explore the park for a bit. Was thinking of driving to The Mural Mile afterwards. Is it worth seeing? (Some of the online reviews mention that a lot of the original murals have been painted over)

Rest and dinner at the AirBnb, then head out to Union Station to see the light show, the fire show, and the whispering arch. My kids love mirror mazes, so we'll have to do that, and they might also convince us to go on the ferris wheel.

Day 4 (Saturday)This is the day to explore Forest Park! If the weather is nice, we'll go to the Boathouse to check out some paddleboats, walk around, check out the playgrounds, maybe visit the zoo. If the weather is crap, we'll just drive around the park, and either head to the art museum or MADE for kids. Hopefully we'll also have some time to visit the World Chess Hall of Fame and the Basilica.

Day 5 (Sunday)We'll have just a few hours before we need to head out. What would you receommend for our last day in St. Louis?

Thanks in advance for any helpful suggestions!