We love split stays and recently did a 5 way split at POR, WL, Poly, BC, AKL. Poly, AKL, and WL are our 3 favorite resorts (love the theming of all three

). We like BC mostly for its location and did POR to check out the Royal Rooms and for its boat access to DTD.
With all that resort changing, we were pleased that we didn't have any problems with Magic Bands, ADRs, FP+ reservations, lost luggage, or checking into or out of resorts.
A big part of why we love split stays is not only to experience different resorts but also because dining is a big part of our WDW vacations and IMO, most of the best dining experiences are in (or within walking distance of) the deluxe resorts. So doing split stays enables us to have a variety of dining experiences in different parts of WDW without having to go out of our way.
Along those lines, we always strategically plan our park days and ADRs to coincide with the resort we're staying at. And we always visit parks on transfer days and use bell services to transfer the luggage (so far, have not had a problem with lost luggage, knock on wood

. Because we're out enjoying a park during the transfer, we never feel "homeless."
We typically book room only, don't bother with dining plans, and buy our tickets separately. We buy
trip insurance through a separate company (Allianz).
One note about making ADRs over the phone and that is, some CM's will let you make ADRs past your first resort stay (at 180 days before your check-in date at the first resort) and others won't. If you get one that doesn't, your best bet is to simply call back and hope for better luck (more often than not, once the CM gets rolling, they'll continue making ADRs beyond the first resort stay).
Applying discounts to a bunch of consecutive resort stays is also an interesting experience (CM's usually think I'm completely nuts

).