Article 1; Section 2 of the US Constitution
"The Number of Representatives shall not exceed one for every thirty Thousand, but each State shall have at Least one Representative;"
In the 1920's the number of Representatives was set at 435. At first blush, it seems that we should have a representative for ever 30,000 people. This would make for an insanely high number of Representatives to the point that a huge stadium would be needed to contain them. The way the law got around this issue was to interpret the 30,000 representatives as the floor for which a representative was needed, not the ceiling. It was decided that there was no ceiling and therefore the number of Representatives could be set at 435 and then reapportioned according to movement of people from State to State with the assurance that a State would have at least one Representative.
In theory you could increase the number or decrease the number as long as the floor was met.
What benefit would be gained by changing the number? Well, if we increased it, you would likely see a strong shift to the Democrats since the vast number of people are in large cities that are more liberal. If we reduced it, then the district lines would become even more heated as gerrymandering took place.
As it is, I see no reason to change the number. 435 is fine.