Mitsurugi, Pyrrha, Patroklos, Leixia, Siegfried, Xiba, Nightmare
they are noob friendly, why would you just focus on one style? try them all! you may get surprised
omega is not that easy, if you compare her to pyrrha she is a hard character because of the 236236B stuff, also her stab:4 is harder to execute, i'd say if you want to use pyrrha omega begin with pyrrha
maxi and natsu are mid, i forgot aeon and astaroth, theyre easy as well
Well if you play nm or sieg you need to learn iaga as their main tools which is definitely not an easy JF (236236:4 B is one of the easier JF's of the game imo in comparison) and you need to learn spacing, sieg in particular is also stance heavy and they require yomi playstyle. As leixia you need to consistently outsmart your opponent and make use of your evasion.
If those chars are on your list omega, maxi and natsu should be too.
you can't compare a 1-hit move with a timing move, you just have to practice the agA which is not that hard to execute while with omega timing is crucial when doing her most important move: double nemesis strike:4
but yea, I have to agree, nightmare and siegfried are "harder" than most of the characters i put there, not harder than omega/maxi/natsu tough, and leixia is very noob friendly i don't know why shouldn't she be on the list