Ugh, I am really wanting to go back to Disneyland too! It's always on my radar with Dug having annual Palm Springs work trips now. And Izzy would be tall enough for RSR, Space, awesome version of BTMRR, etc! Your trip sounds great and I'd love to do one like that someday. I've been thinking when Izzy's a bit older that it would be great to do a car trip driving Highway 1 and such (I've done that solo a couple times and loved it).
But back to the Disneyland travel day! Sounds rough to travel with two little ones and a not-super-helpful older one, but you handled it well. Glad that things went reasonably smoothly and you got to enjoy some pool time. Yay for Aria trying (and liking) the big slide. Izzy would love that one too.
I'm surprised you managed a midsize! We've been getting full size and it's only us 3 (and a stroller and a bunch of bags). The discount I use (from my old employer

) has the same rates for everything up to full size, so might as well. Or I can usually get them pretty cheap through Costco, depending on where I'm traveling. I'd have a hard time getting anything smaller now.
Can't wait to hear about your California Adventure time!