I'm just seeing this now, but I hope you have a chance to read my reply. We've been to Sesame Place twice (once with a 1, 3, 5 year old; once again when they were 3,5, 7 years old). Both visits were precious. The atmosphere is so positive. Remember those original Sesame Street songs that we knew when we were small? They play as the sound track in the park, making it nostalgic for mom and dad, and magical for the kids. Characters have meeting spots, but you can also find them free-roaming with their handler on their way to their spots. I remember my Count loving son catching his eye from across the path, Count walked up, took my son by the hand and they walked hand-in-hand to the Count's splash pad. Incredible.The first time we went, I didn't really have in my head just how much of the park is water features. Definitely expect to be in the water most of the day. Both of our visits were in July, and lines were never prohibitive. Same with characters line ups. I could go on and on about this place, but I'll leave you with a few take-aways (unless you ask for more info, in which case, I'll spill my guts).
It's not Disney. It's much smaller. 2.5 days was good for us, and that included returning one evening for the parade. The scope of the park is not intimidating, meaning you can cover it all (every.nook.and.cranny) easily in 2 days. This suited us just fine. The boys wanted to ride Oscar's Rusty Rockets a dozen times, and I just let them. We weren't in a hurry to get anywhere else. It also can't compare with food. Expect it; it's typical amusement park fare. There are plenty of cute souvenirs that come with the dishes, so stash them away and take them home with you. Likewise, customer service isn't exactly the same standard as Disney, but we had overwhelmingly positive experiences.
Some of the signage says you can't bring in food, but you can. We brought a small soft cooler (that fit in the middle part of our sit-and-stand stroller) and snacked all day from that. Skip the preferred parking. The regular parking is still just a stone's throw from the entrance if you're comparing to Disney parks.
I hope you have a lovely stay. The first time we stayed, we used a promo package with a recommended hotel but those 10 miles felt really long in rush hour traffic, especially when we had a 1 year old who was zapped at the end of the day. For our second stay, we stayed at the location directly across the street (I don't remember... a Double Tree, maybe?) This was fantastic because we could return to our room, jammie down, get a break from the heat, and then return for the evening parade (which is the same, but with glowing features.. cool to see if a return to the park isn't a big to-do).
This is turning into a big reply. Ask any follow-up questions!