I have the advantage on not having been Disneyfied, so my opinion is unbiased in any way. Just came back from my split WDW/Universal (and IoA) vacation. It was our first time to any of these parks.
We loved all of it! We saved Harry Potter/Universal for last and were fully expecting it to be a letdown from WDW, but were pleasantly surprised at how much we loved it.
IMO, Downtown Disney is more like a glorified mall. Albeit a very nice and entertaining mall. Citywalk seemed more lively, exciting, visually stimulating and fun to us. YMMV.
No fireworks at Universal. They do them only for major holidays like July 4 and New Years Eve.
We were there for Universal Mardi Gras. We loved the parade. The floats were beautiful! But then again, we had a blast at MK's and DHS's afternoon parades (I will never again hear "I Just Want to Bang on the Drum All Day" without smiling) and the Electric Light parade at MK took our breath away. Edge goes to WDW, but props to Univ. for a tremendous, festive atmosphere (and tons of beads!).
We don't do water rides but if it's really hot, I hear that Universal's rides get you soaked. This is not for everyone (I'm like a cat - don't like to walk around wet and chafing). We save our getting wet for the hotel pool. Edge for us was RPH pool > POP. But really apples to oranges there. Both were fabulous.
IMO, no rides were better than Harry Potter Forbidden Journey, Spiderman, and the Simpsons. These rides were cutting edge technology, perfectly themed, humorous, thrilling and not too brief. They were incredibly fun, and we were fortunate enough to do all of them multiple times. The closest fun rides at WDW for us was Star Tours and Buzz Lightyear which we did three times each. I must add here that we are not coaster people. We only do virtual reality thrill rides. I thought Mission Space Green was nicely themed and all, but not so great. But DD refused to try Orange.
MK tugs at your heartstrings in a way that Universal just doesn't. But it's all good. We really pulled out all the stops and made the most of this vacation by doing all the parks, but you can't go wrong by going to Universal. Just have an open mind and if you can financially swing it, stay onsite or pay extra and get the Express passes. No waits for the best rides (HPFJ is exempt). If you stay onsite, you get early admission to IoA, which will be great for you to beeline over to HPFJ and Spiderman rides.
I'm a visual person and love the little details like landscaping and flowers. I thought Universal was very clean, extremely attractive and prettier than I expected. The shows can't be beat either. We loved the Beetlejuice Rock 'N Roll Review and the Animal Actors shows. The sets were really great too. At WDW, we loved Fantasmic, Philharmagic, American Idol, Monsters Inc. Laugh Factory, Turtle Talk with Crush, HoP, and the movie show at the American Pavilion and more. WDW > Universal for offering more shows. But Universal did a great job had lots of good music piped in all over the park (maybe just for Mardi Gras?, I don't know, but we enjoyed it).
