There could /still/ be one case I forgot to mention 
Compiler Optimization Flags.
Certain compiler flags (man gcc?) have an effect on trading execution speed/performance for size: because not /all/ machine code duplication is /always/ bad - if all 'repeatable' code is split into 'sub-routines' you get significantly less machine code to load; but the cost of 'jumping' to the repeatable sections can be high, especially in tight loops (jumps can take time especially if cache / tlb is reloaded) but on the other side of the coin is, loading large binary into memory increases cpu cache misses too, which is bad, too (again this place is to small to explain all that) Proper answer, i guess, usually is: first you try, then you know which is better for you
Which (again) is (should be) controlled by either the ./configure flags or switches or the make menuconfig step. Or in the code of either script itself.
Other than that, why do you care so much about the size of it? If it works, and doesn't give 'odd' behavior like 100% cpu in normal conditions, based on official description, and is able to verify itself working, I probably wouldn't care all /that/ much