I was going to PM you about your characters anyways, but I'll re-watch your matches and I'll give you and suggestions if I see any.
I just watched your match with Charex. First of all, Charex is a strong player (which is one of the reasons I disappointed we couldn't play that one weekend as he was on my to-do-list); it seems like You were unfamiliar with his characters Clark and particularly Iori rather than making gross mistakes yourself.
On your first match, Iori kept keeping you out with his specials. Learn which ones are punishable and which ones are not. One way of checking in training mode is select two Ioris, set the computer to "guard jump". Then do his qcb+B and hold up immediately. You can tell who has the frame advantage and roughly how much by when they jump. Then repeat it with other specials. The reason for choosing the same two characters is the jump height as everyone is different. You could technically choose it for Andy and Iori if you wanted to as well but it's a little harder to discern the difference but doable.
I was only recently introduced to this method by Kunio at Evo, before that it was a lot of painstaking trial and error.
I'll keep updating as I watch more of your matches.
EDIT: Second match against Clark, you're not poking enough against Clark.
As a Clark user, it's hard to get into a Shen player who knows how to zone well with his normals. Once again, the Clark wake up games that got you, the general rule is hop vertically against 1-framer grapplers like Shen, Vice, Goro, Maxima and Clark (I might be missing others but you get my point). Clark's main anti air is his Gatling Attack (c.b~f+P) which works decent against hoppers but horrible against jumpers; keep that in mind. I also noticed he likes doing d.C into his SABB command throw which is interesting; I'll have to try that myself (I like using s.B, s.D, SAAB).
The second Iori match you did much better and zoning him out, be mindful of his command grab since it's technically 5+ frames (the Ex one is 5 frames, and the normal one isn't list but we all know the Ex one is faster). Raiden tips, I'm no expert and to be honest, you guys in Norcal has much more Raiden matchup experience than we do as we don't use him at all in the arcades, none of us do, and only 2 ppl use them for tourneys. Having said that, you're only relying on strong pokes, use his light pokes as well so you can dash in to command throw them (if you're only charging one dropkick). If you're charging both, the do a dash normal throw.
Lastly, just watch your shallow jump ins, especially against Clark since he has a command throw that will punish you. Overall, there can be improvements but Charex is a strong opponent and once again he was one of the 3 ppl on our to-do-list when we came up so don't be so hard on yourself.