I see that LG offers some nice 3535 LEDs:
Sorry, no link, LG site is so dynamic that I fail to produce a working url.
Looking at the datasheet, thermally they are a bit worse than XP-L or LH351D so may be unable to match their output.
Vf is lower.
Efficiency is good.
CRI70-90 though 90 is available in neutral and cold tints, 5000K and up.
Interesting die shape.
May be good for flooders.
Availability? Quite bad.