well, for one, this is theory fighting to the max. You do not know how your opponent will respond to your mixups.
Your first mixups starts with 2 jabs which is dangerously easy to parry, people will just have to tap any way and tadaa, free hits. Now lets assume they didn’t parry it because they didn’t figure you were gonna do something that stupid, lets assume they blocked, you entered jab twice and you’re at perfect s.MP range which if it hits can be converted to super. Now the question is: how do you intend to land that s.MP?
There’s 2 cases: midscreen and in corner, in midscreen any decent opponent will be walking backwards, right out of your offense, this means you will lose your perfect s.MP range which narrows down your usefull normals to your kicks. If either of these kicks whiff, or gets parried you WILL get punished. So preferably you would want to keep that s.MP range and you will be forced to either give up on the thing all together or give chase, which means you’ll lose your own defense in the process.
In corner you’re off a little better since he can’t walk out of range, however as you stopped after the double c.LP there’s still room for the c.LK, which can be launched by either character, and that’s 3 frames from the c.LK vs 6 frames from the s.MP, is the most general case you won’t be using s.MP. Even if he decides not to interrupt your chain, the s.MP will be hitting a block, since there’s no fear for throws or overheads, because you placed yourself in the precise range that neither of them will convert into super.
You cannot buffer UOH iirc, I’ve not been able to do it myself, I’m not really the buffering kind though. There is a meaty UOH timing that will allow you to shoryuken and karashoryuken. After SA3, do 2 dashes, c.MP against another shoto, wait a bit then do UOH, that should be the timing. If any UOH gets blocked the recovery on the UOH is indeed large enough to allow a throw follow up, This also means it can be throw punished or punished with a normal such as c.MK. Also note that Ken has no usefull karathrow.
On the 3rd, the c.LK,s.LP can actually be buffered, if the opponent was crouchguarding the shoryuken wont come out because it can’t cancel from the s.LP, so if s.LP connects its pretty much guaranteed hit. Now if the s.LP whiffs, there’s 2 options that break your opponent’s guard, those are (no, not the MPs) throw and evade throwtech into punish. The evade throw tech depends on how they tech, if they tech without option select you can backdash c.MK XX SA3, if they do option select you can parry down and punish or walk out of c.LP range and whiff punish.