While j.H nets extra time with hit-stun and CH is pain, j.2S is actually very easy to combo off of. (j.2S followed by HS will generally always work) Generally, my midscreen oki doesn't change with the character as it tends to work very well. After a grab or icespike FRC:
2xHS Fish -> IAD -> reverse AD -> j.2s -> j.HS -> land -> close S -> laser fish -> K -> S -> HS -> 236HS
alternatively; HS Fish -> P Fish -> IAD - Slash Bubble -> j.HS (Pop Bubble and overhead)
2xHS Fish -> IAD -> reverse AD -> land -> c.2k etc.
I would understand if these are basic and obvious, but it's generally how I try to change up midscreen oki. Although, I tend to spam j.HS too, because, sometimes, it rapes for free.