load times? how? are you saying that the code is so big that it lags to put it in a file and load it? if so why does things like jquery work fine? seems sus
if your code is over 15k lines im pretty sure a problem might exist, what on earth could take up 15k lines.
Also if it's only a few milliseconds, it would be easier to disperse it into scripts like "elements.js" just to make it like 1000% easier to add new code, instead of searching 15k lines
if its all dispersed into seperate files you would have to add the source to all of them in the index.html and that would be quite hard, and there are some comments that break it up into sections