Yeah, I get what you're saying, I don't know the answer, but I've wondered the same thing. You'd think an প্রবন্ধ would be worth আরো than an প্রতীকী because it takes আরো work, but then again, how can they really measure it?
i couldn't say প্রবন্ধ as i don't write many, but if আপনি were add like 20 প্রতিমূর্তি to one spot and 20 প্রবন্ধ to another, i'd Imagen you'd get a medal for the প্রবন্ধ spot, i think it works with the harder it is to add to the spot its worth more, for example it's not hard to type into goole pictures of cheese (for the cheese spot of course) but imagen trying to write an প্রবন্ধ about something.
so yeh, i'd say some things are worth আরো than others.