ChicagoJ, I can completely relate to why you are concerned...I have sooo been there myself!
I don't know your exact situation, but as for me, I am a SAHM to one now-16 year old daughter who we've been taking to Disney World for a week every year since she was 2. As a SAHM and "planner in chief" for my family (and because I am type A perfectionist), for some reason I would always put a burden on myself of making the vacation perfect -- the perfect ADRs, the perfect hotel, the perfect schedule (using a crowd tracker from one of those Touring guides), the perfect time of year, etc., etc. I would be so stressed out every year by the time we got to WDW that I would be cranky for the first several days of the trip because I would be so worried that something would go wrong, or that we'd get off schedule, etc.
I have no idea if you're like me with respect to the stressing out/type A/perfectionist thing, but I shared all that to just reassure you that I think you have made great choices and that it will all work out very well, and here's why.
When our D was that little (yours is 6, yes?), all the walking/traveling from park to park was a HUGE deal. And I can tell you as someone who has stayed at all the Deluxe resorts that I think the Poly is the best choice in your situation. The fact that you can walk to the TTC to take a Monorail directly to Epcot, and can catch a direct Monorail to MK, is priceless. Is the Poly my favorite resort in all of WDW in terms of the actual hotel rooms and accommodations? No. But it is lovely, relaxing, the grounds are lush, the quick service food offerings are fantastic, the service is great, the rooms are very nice, and when you have an exhausted 6 year old at the end of a park day (or who desperately needs a mid-day park escape back to the hotel), that quick monorail ride and/or short walk from the TTC to your room is, once again, priceless. In my opinion, it provides the easiest, quickest, most hassle-free transportation options to MK and Epcot...and when our D was little, that mattered more to us than anything else (those monorail lines can get long if you get unlucky and hit them at a bad time!). Plus, there are so many extra little fun things to do at the Poly for kids, as others have mentioned, that I think you will be very happy with your choice. Now, is it as nice as, say, the Four Seasons or some other high-end resort that you'd find in a non-Disney destination? No (and I know that stinks because the Poly is so expensive). But I have learned over our many trips to WDW that different things will take priority on a go-go-go type vacation like WDW as opposed to one, say, in Hawaii or some other "relax on the beach" type destination. Truly, I think you will end up being very happy with your choice of the Poly.
And then, with respect to your restaurant choices -- again, I think you will be very happy with them in light of your daughter's age and what you are looking to get out of those experiences. I can't speak to Ohana because we've never been (we are vegetarians and one of us is allergic to soy, so we couldn't make the tofu substitution work), but I've been to all the other restaurants you booked and I think they will work out great. We have absolutely priceless photos of our D as a 4 year old at CRT...the princesses made such a fuss over her, she loved eating in a castle, and she still mentions that meal to this day...and the food was good! Is it overpriced? Yes. But has so many other posters have mentioned, pretty much everything is overpriced at WDW, so you just kind of have to have amnesia on that point (and honestly, for us, the dining plan makes that easier). Very similar experience at Chef Mickey's -- D loved the fuss the characters made over her (and it saved us from waiting for hours in line to meet them at the parks), and the food was fine (although I will say that I think the breakfast there is better than dinner...but that's just my opinion, and the opinion of a vegetarian at that, lol). And as for the San Angel Inn, call me crazy, but I really like the food there...and I've lived most of my life in So Cal, where we have incredible Mexican food! We first went there on our honeymoon in 1994, and yes, the menu/ownership/etc has changed over the years, but we've never had a bad experience there, and the service has always been fine. Is it the best Mexican food I've ever had in my life? No...but it has always been more than satisfactory...and we think that the setting is just gorgeous and the river with the boats floating by always managed to entertain our daughter too.
I believe you also asked about favorite restaurants at MK and Epcot...again, I will answer that question with an eye towards your D's age. At Epcot, I ditto the recommendations of those who mentioned Biergarten...I really worried about that one the first time we went, but they have a ton of kid-friendly choices on the buffet, and my D loved the band and sitting at the big communal-style table with other families (and H and I actually thought the food was really good and had a surprising amount of choices for vegetarians). At MK, LTT is also very kid-friendly (can't go wrong with mac and cheese and mashed potatoes, right?), and my D loved seeing Mickey and Minnie and the gang in their colonial attire. I think your D would love BOG, but it's such a tough reservation to get that I wouldn't sweat not going since you're doing CRT. I'd keep checking to see if a lunch reservation happens to pop up...but again, no biggie if you miss it...at age 6 your D won't remember that you didn't get to go there...she'll remember that she ate in Cinderella's Castle with the princesses!
I just asked my H if there was any restaurant that we absolutely would never go to again, and we could only come up with one...Hollywood and Vine at the Studios...and I know that there are plenty of people who really love it! For us, we had a lot of trouble with the noise factor there...it has been probably 8 years since we've been, but at the time their decor was very "shiny metal surfaces-looking", so all the sound bounced off that and there was nothing to absorb it, and we left with terrible headaches. But despite that, our D remembers it as one of her favorites, because at the time they were the only TS that had the Little Einsteins, and that was her favorite show (and the Einsteins led the kids in a parade, which greatly contributed to the noise factor, which D loved but H and I hated, haha)! I also remember there being not many vegetarian choices on the buffet...but that sort of proves the point that several people have made, that reviews are so specific to the reviewer...and sometimes people don't elaborate on why they don't like a particular restaurant/hotel. So if noise and veggie options don't matter to you, my opinion of H&V would be pretty useless!
One last thought I will leave you with...I specifically remember being stressed the first time we booked at the Poly because the resort was supposedly undergoing renovations, and somebody had mentioned in a review here on the DisBoards that the decor reminded them of the Brady Bunch's trip to Hawaii episode! I remember freaking out at the very high holiday rate we were paying to stay at what someone had called a "tacky Brady Bunch" resort! But I can assure you that when we got there the decor was neither tacky nor Brady Bunch-ish. And I never even noticed the renovations that were supposedly underway! It ended up being the first of several wonderful stays at the Poly...and I'm betting yours will be the same.
Best wishes for a fantastic trip!
Plus, you can see Illuminations if you time it right) 
Rose n Crown is another great atmosphere place where the food is equal to it. Biergarten is my final place I name in Epcot, reason why, its over the top in atmosphere, the band makes it even more appealing and the food is drop dead good.
