I know a good amount about these matchups, it's all good haha.
Lucky for you I've been running into a lot of trouble against these two characters in the last few local tournies I attended.
For Ken, you just have to be really on point. If he knows what he's doing he's going to keep the perfect distance to where cr.mk doesn't hit you, but will catch you if you dash so he can SA3 for free. A good Ken player that can parry really, really puts Alex in a tough spot. You have to do your best to mix things up while maintaining pressure, and that's not easy. Use the command grab and Alex's kara grab (f.hp + grab) as often as you feel you can, and don't press any unnecessary buttons. One parry could be your death, because once Ken gets a knockdown on you, it's hell for Alex.
For Akuma... well, it's really annoying but you actually need to learn how to red parry for this matchup to be any easier. Akuma's tatsu is pretty damn safe against Alex. If you can consistently red parry it then you limit his pressure by a bit which you really need. Demon flip is pretty hard to deal with for Alex, as he's big, and his anti air normals aren't that great. Your best bets against it is to dash, if you can see it coming, jump hp, or f.mp. If you can't react fast enough, just block and dash at the next opening.
Don't forget about Alex's kara grab, it's really good. Alex is all about rushdown as well as a large amount of calculated defense. Just keep playing, playing playing