I love
Louis! I think it would be a great idea to use as an honouring name.
Louis and
Miriam are ok as siblings - they don't seem overly matchy or a perfect fit, but good nonetheless.
That's the same problem I have with
Eliana as well - too trendy sounding. Using it as a middle name could solve that problem, it certainly is refreshing in the middle name spot!
Judith Eliana is good in flow, but the names are really mismatched in style in my opinion.