At various points, I've been a regular guest of both WDW and DLR, and have made multiple visits to all the international parks excluding Shanghai. I think that each location has its own merits, so on one level it's tough to compare them, but it's also inevitable
DLR is jam-packed with rides and a good place to spend a couple days. WDW is more spread out, and makes for a much more well-rounded vacation experience over more time. I wouldn't want to try to do all of WDW in 2-3 days, and likewise I can't imagine spending a full week in DLR.
With any of the traditional metrics for comparison (rides, entertainment, food, etc.), there are pros and cons to each, making it mostly pointless to do a one-by-one analysis. I will say that as far as crowds go, I would much rather be surrounded by the "unaware rubes" in WDW than the "entitled APers" at DLR; neither are perfect, but when I'm on vacation I prefer to be around people who treat it as a special experience, not a weekly occurrence
Internationally, TDR has the best maintenance, cast members, and entertainment roster of any Disney resort. That's simply undebatable. TDL is a little sterile and looks like it was designed by committee (which it was, since WDI's top crew was busy with EPCOT Center), but TDS is spectacular, and a real tour de force of WDI's best work, and the park's broad theme allows nearly anything to fit in seamlessly, just like the original DL concept. Most guests could easily spend 3-4 days at TDR, especially with the infamous crowds they get at certain times of the year
DLP has all the charm and intimacy of DL, but manages to make it work on a significantly larger scale. WDSP has a handful of fun attractions, but struggles to fill more than a few hours and is the ugliest Disney park in the world. The resort has been saddled down with debts from the original overbuilt hotels, and they've struggled with money for maintenance and park additions ever since. Things seem to be heading in the right direction, but the DLRP saga is such a rollercoaster that it's hard to tell. 2-3 days is probably enough to see everything
HKDL is a small park with few attractions (granted, my last visit was in 2010, before the mini-lands opened) but what's there is done very well. Of the cloned attractions, their versions are the best or very close to it. The resort area is a beautiful secluded oasis from the hectic city, but it still seems to lack the content to really pull people in and keep them in. 1 day is plenty for this one
I see the merits of each resort, and can appreciate what they bring to the table. Similar to how a ski trip and a cruise are different types of vacations, I enjoy the differences between the various Disney locations. If I had to pick between DLR and WDW, I would probably say WDW simply because it takes more time and can fill a vacation better, considering the hassle of physically getting to either location for me
If we're talking about the parks individually, DL is the clear winner domestically, probably followed by Epcot, then DAK, DCA, and the Studios. Spots 2-5 all have their flaws and struggle to really fill a day on their own (though it's possible at any of them), but are all generally enjoyable parks with a lot of fun and worthwhile elements
As a controversial opinion, MK is my least favorite domestic park by a long shot; it may even be my least favorite worldwide, though WDSP gives it a real run for its money. It's not that MK doesn't have the bones to be a great park (as discussed earlier in this thread), but the operations, crowds, and lack of real expansion have made for a situation where it's really just a difficult place to enjoy spending any time. At least WDSP has the novelty of being in a foreign country and relative lack of crowds to help it along