You will love it! It's much more go with the flow, so try to not stress too much about pre-planning. Make sure to watch a few videos about LLMP at DL - it's much simpler and easier at DL (kind of like the old
Genie+ at WDW but better). There's also far more rides per park at DLR which makes it easier to get lots of value out of LLMP (and lower standby waits for similar rides). LLSP is also really easy at DL - you can easily grab a time day of and they don't run out.
The main thing to pre-plan at 60 days is meals, but there's fewer table service options at DLR and lots of really great counter service. In terms of nighttime show planning, the package I most recommend you consider is a Fantasmic dining package. You get a good spot to watch the show and fireworks right after! PTN might be worth considering depending on reviews from May 16th and after (when the parade starts its summer run).