Yeah, it's a tad redundant. Ellis is an awesome name, though.
Elle Heller is not good, as the entire first name is right smack dab in the middle of the last name. Ellis Heller / Ellie Heller are better, but the repeated 'ell' is still prominent. Even one L as opposed to 2 would soften the impact, as in Eloise Heller. Of course that's a much more feminine name. Are you looking for other unisex/non-frilly names?
I am looking for a non-frilly name. Unfortunately, I haven't found anything else we seem to like or agree on, with the exception of Ellis. ...And I agree of the redundancy. Was just hoping to hear otherwise. :(
Take a quick looksy through this
I don't know if this is an option for you, if you really like Ellis, an hyphenated last name ("Ellis Johnson-Heller") would be a good way to make it work.
Aylett Heller ("noble battle")
I love Ellis, but yeah ... I don't think it works. I definitely wouldn't use it. It has a similar sound to 'Helen Keller'. Elliott is similar and sounds better with your last name (in my opinion). Even Elsa sounds a tad better (still probably wouldn't use it, but I don't think it's AS bad as Ellis). Here are a few other no-frills options: