Stevo i've come terms with Joker's lack of mix up midscreen lol
Just play to get to ther corner, any combo you get midscreen I think of it as just bonus damage.
Against a good opponent, you aren't going to open them up for significant damage.
That being said this is what I generally run.
Characters generally fall into one of these two categories
Characters who can duck 2,1 but not 2,1,2 and characters who can duck 2,1,2 but not 2,1
Against characters who can't duck 2,1,2 i'll run that teeth mix up all day. If they pressure i'm ready to push block and take my 25%. Usually people will just jump away. Which i'm fine with since it pushes them closer to the corner. If im feeling ballsy, i'll chase the backdash/jump away with j3 for that bit of extra damage and wall carry. But if I decide to just block, it is no biggy. We are reset to neutral but hes closer to the corner.
Some times if i have spare meter i'll do the entire 2,1,2 mb rlg. People tend to panic and try jump out (taking advantage of lack match up exp here but it is good to throw out every once in a while.) Even if people block it isnt too bad because we get extra chip and we get the semi safe jump 2 back ii. People who dont respect the safe jump eat the j2 for full combo or take the air to air for a mini 25%ish combo.
Against characters who can duck 2,1,2. I run the 2,1 frame traps. Generally mixing up between 2,1,3 and 2,1 b1. People can react to the 2,1 pause and block the b1. However then we can just loop 2,1. Or do 2,1, b2 or 2,1 grab, or 2,1 crowbar. We don't get much damage but all these enders give a lot of wall carry.
We do need to be wary of mb b3 cuz it will beat the frame traps. We can beat this on a read with parry or own mb b3 though.
Characters who can duck both options, which I believe is only Shazam, are a nightmare. We just have to run 3,2,3 and take the +1. Or do 3,2 acid flower for chip. Fighting a high level shazam is going to be horrible imo. One of jokers harder match ups cuz he takes away the whole 2,1,2, series, has a decent d2 to aa and has a good air to air game with j1 and j2. Also we can't punish torpedo for much damage, and he gets out of our set ups free with his teleport.
Might be better after I get some more exp, but theory wise it spells a bad match.
Overall, I just base my game around slowly chipping away at their health midscreen, concentrating more on the wall carry aspect. If I touch them thats great, I take a huge chunk and get a good mix up. Otherwise, i'm content with chipping away because I know once I get them to the corner it's horrible for them. Characters with good corner escapes, e.g. BA, Gl, Shazam, Ares, Zod, make this harder. But we just need to space our selves better in the corner to catch escape attempts. We just can't be as aggressive on knockdown.