I have a few bits of advice for Ahgao too!
My first suggestion would be to work on timing for your punishment. When people were whiffing Shoryukens/etc. against you, you’re usually using a throw or an EX Danku to punish. Moves like that that leave you wide open should be punished more severely. I understand if you have to dash in or otherwise simply don’t have enough time, then a throw is better than nothing, but when you block a Shoryuken right in front of you, you should be able to land at least a c.HP > heavy Danku when they come down. It’ll take some work to get that timing down, but it does twice as much damage as a throw or an EX Danku. Remember, the EX Danku actually does less damage than the heavy Danku, a tradeoff for its speed.
Rather than using the EX Danku to hit whiffs, you can use it in situations where it does things Dan can’t otherwise do. I’ll use Ryu as an example from the last video. His sweep is technically an unsafe move, but it pushes you back so far that you generally can’t hit him before he recovers. Dan has two moves that will still allow him to hit: His Ultra, and the EX Danku. If you block a sweep from Ryu, you should immediately pop off a reversal EX Danku to punish him for it. The Ultra is better, but that’s a lot tricker of a motion to squeeze in during the blockstun. 
Similarly, you can EX Danku (or Ultra) between the two kicks of Guile’s sweep.
In the Ryu match, in the first round in particular, you Focus absorbed an awful lot of fireballs in a row. It paid off to some extent in giving you a strong Ultra to land off the FA, but that’s still a very risky move. You’re probably better off using the FA to absorb one fireball, then dodging the next to allow your lifebar to recover, then FAing the next, and so on. Once you got a big chunk of phantom health, the Ryu came after you in force just long enough to score a single hit before retreating again. The risk vs. reward just wasn’t in your favour there.
And a final note, I liked the Blanka match, it’s one of Dan’s harder matchups. Using the jabs to bait out his reversal Ultra is something I do myself, though that’s another case where after blocking the Ultra, you’ve got a big window for a c.HP > heavy Danku. My word of caution to you is to avoid throwing non-LK Danku kicks at a Blanka who’s got a charged Ultra. If he does his Ultra as a reversal off the Danku kicks, you’re helpless to block it and he gets full damage on you. Dankus are great against a non-Ultra ready Blanka, but once he gets his Ultra, you’ve gotta restrain yourself until you can bait it out. It’s the same with Zangief, his Spinning Piledriver will devour a blocked medium/heavy/EX Danku if he’s smart enough to do it (you’d be surprised how many will try to Lariat instead). You need to take those moves out of your arsenal entirely against him, except for punishment combos.
Oh yeah, I remembered one last thing: On those occasions where you wind up doing a jab/light kick combo string, always try to finish it off with a standing light kick. That standing light kick has longer range than Dan’s other jabs, which can let you string one extra hit on beyond what you could normally get. It’s pretty small damage, but every bit of guaranteed damage counts.
I don’t want to seem overly negative, there’s a lot of good stuff in your videos. A true Saikyo master always improves himself though!
.
