Since page size is a power of two, no comparison or addition is necessary. Just do table lookup and bit substitution. Easy to swap since everything is the same size, which is usually the same size as disk blocks to and from which pages are swapped. The larger the page, the worse this is. Each segment contains one or more pages.
Segments vary in size and are often large.
Instead of having a single page table, have many page tables with a base and bound for each. Call the stuff associated with each page table a segment. Page table entries are only 12 bits, real addresses are 24 bits. If a segment isn't used, then there's no need to even have a page table for it. This stuff goes over hard.