Interesting. I've only heard constant praise on Tokyo Disneyland but I'm guessing that's mostly because of Disney Sea. Another way to put it, if Tokyo Disney sea didn't exist, would it be worthwhile for a DL vet to visit Tokyo Disneyland - solely for the resort? I recently saw a picture of Tokyos FL and it doesn't look great. Also, looking at the attraction roster, Poohs Hunny Hunt is the only unique attraction that peaks my interest. Not saying that we should only judge by attractions. For example, I know that DLP is supposed to be a beautiful park so I would like to see it even though there aren't any unique attractions we don't have stateside, excluding their Studio park.
I prefer TDL to MK, but not to DL. TDL's World Bazaar and hub area are unique and beautiful. Pooh is great, as is Monsters Inc. (although neither are really E tickets). Their Jungle Cruise is tops worldwide. The whole Westernland/Critter Country area is stunning and features far and away the nicest Splash Mountain installation. The River is pristine and fantastic. Country Bears in perfect shape.
Fantasyland is weird. It feels like it hasn't been updated ever, because it hasn't. It's like an Orlando time warp other than the placement of Haunted Mansion there. Tomorrowland is hilariously outdated, but still pristine. OLC is finally starting to address the Fantasyland/Tomorrowland areas, and I'm looking forward to that improving over the next several years.
Entertainment and seasonal events are unmatched by any other Disney park. Dreamlights is insanely beautiful and unlike parades in the US, regularly updated. Happiness is Here is the best day parade worldwide at present. The event parades (Frozen, Easter, Halloween & Christmas) would qualify as full length parades at domestic resorts.
What makes TDL shine is that it's pristine. There's no other word. The upkeep is incredible, the cast is superlative in every way, even the food is good (Queen of Hearts Banquet Hall is a can't-miss). You'd be surprised how easy it is to overlook things like old timey Fantasyland when the standard of operation is so unbelievably high.
All this to say, DL vets should absolutely visit TDL, but if you only had one day in Tokyo and had to pick, TDS would be the obvious choice. On my last Tokyo trip, we spent 1.5 days at TDL and 2.5 days at TDS, and wished I had more time for both.
DLP does have some unique attractions. Phantom Manor in particular - it's an HM, but not really - it's its own beast. Its walkthroughs are second to none and there are several. DLP overall is worth visiting to see Baxter's vision of a modern Disneyland. It's truly incredible.