Sometimes all is said in done in less - just because there is a "standard" does not mean that every works must comply to it. Though I tend to find that fantasy that is not a DnD or "traditional" in theme tends to work better with a longer book - as there is more space to develope the world and ideas within that world.
But if your tale is done, there is really nothing to stop you trying to get it out there - just make sure that it really is done to your idea of perfection - and though its painful to recive - be ready for regections (not saying that they are going to happen, but its not impossible
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