Your suggested translation is good!
The only correction is that I would change pluria to plura.
(See this unanswered question for a brief discussion of the two.)
I like your word choices paucus and plus, so I would go with e paucis plura.
The plural plures/plura is a good translation for "many".
The singular plus is close to "much".
The Latin and English words don't match exactly, but this rule of thumb should take you to the right direction.
It is worth noting that plura is neuter, meaning that the "many" are things.
If you want to refer to many people insted, use plures.
The ablative paucis looks the same in all genders.
The words paucus and plus do not seem to refer to any specific nouns in this use, so the distinction is between things and people.
The actual US motto has the neuter unum, so plura is the most analogous choice.
Another joke variant of the US motto was discussed in an earlier question.