Akuma’s not really all that newbie-friendly. He can do many of the same BASIC links and combos as Ken/Ryu, but in order to do real damage you have to learn more involved juggles and stuff like fancy ways to buffer Raging Demon…and if you make a mistake with Akuma, you pay a much steeper lifebar cost.
Bison and Blanka are both fairly easy characters to pick up and play, in that they have both relatively simple combos and a fairly simple strategic interface. They’re kinda two sides of the same coin, where Bison relies more on safe pressure and poking, Blanka relies more on crossup trickery and fakeouts into throw knockdown (which set up or continue his shenanigans).
Balrog is probably even easier than the above two to play, as he has more reliable ways to land Ultra I off of similarly simple combos, as well as some good option selects, good normals, and disgusting tick-throw setups. All three of the above characters have a decent amount of life/stun so you can afford to be a little sloppy when learning how they play.
Of the fancy new characters, Dee Jay and Cody are probably the easiest to pick up and play; they both have some easy links into combos (Cody’s c. LP, c. MP has GOT to be the EASIEST jab-strong link in the entire game) and decent life and zoning ability in exchange for some deficiency on wakeup (and Cody’s slow-ass walk speed). Most of the others are more offensive-minded with higher execution and strategic barriers to overcome.
As for charge vs. command…speaking from MY experience, I’d say charge characters are probably easier to learn in general, because they tend to get easy-linking/strong poking normals in exchange for having to put up with charge time, which tends to simplify most of their BASIC combos (stuff like c. LP, c. LP, c. LK xx special), as well as decent mobility to make it worth abandoning charge. It also seems much easier to learn how to manage charge time so that you can more easily turn semi-random hits into a quick combo since the dexterity barrier is lower (you hold back and/or down, you hit buttons, if you see them hitting in a favorable way, you whip to forward and/or up + button[s]); you don’t have to worry quite so much about panicking and cancelling/not cancelling into a special move at the right time because you weren’t prepared to do the motion.