Harry Potter and the Natural 20 has a lot of characters optimizing in interesting ways in response to the constraints of their universe, but their universe's laws are a lot less realistic than Worm or HPMOR. The Ethshar books by Lawrence Watt-Evans are not one coherent story but there are a lot of books set in the same world. Miles Vorkosigan has the whole "cunning main character thinks outside the box to beat impossible odds" dynamic and there are a bunch of books that follow him and his life, although the fact that he ages throughout them gives them a pretty different feel than the chronologically much shorter timespan of HPMOR.
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