Eliot's more difficult to use in comparison to Ein though I personally prefer Ein cause of his theme, 46P/236P and those shades.
EIN! Not enough Karate masters... Then again there also isn't alot of Eliot rep either haha Eluot is better than Ein though.
Go with Ein. He's REALLY easy to pick up, and he doesn't require much muscle memory. I use three mains and still can cram him in, and I'm sure you can do the same with Helena and Jacky as far as complexity is concerned
I got Amer--02 & ClassicMorris teaching me Ein, so I'll probably get the hang of mastering Ein in no time.
Besides people I know are catching on to my Jacky more than my Helena so Helena is kinda safe but Ein will be unpredictable