I'm starting to really, really like 2A 5B 2C 623A 214A as a setup starter. Obviously it's not the most damage, more meter combos would do more, but the height from the 2A 5B 2C 623A gives a lot of time to 214A and then do a setup.
Also, 2A 5B 5C 6C 623C is a reliable way to get into a 2B BE2C loop, and this obviously can be ended with 623A, or a 214A xx 623C again. So basically either
2A 5B 5C 6C 623C [2B BE2C] x N 623A 214A dash mixup
2A 5B 5C 6C 623C [2B BE2C] x N 214A xx 623C j.236A dash mixup
This is really nice because this is basically a 4.5k damage combo that ends in a really good mixup, as opposed to a regular combo which is admittedly more damage, but doesn't allow for as good of a mixup.
Notes: Seems you can only get up to three 2B BE2C's. Also, 2AA or j.A 2A is acceptable, but any more A moves and the combo will stop working on some character, in particular Kouma for sure.