As has been pointed out, there are a lot of variables to check before worrying about the paper. Quality of lens and coverage for the format, enlarger alignment and possible vibrations in the enlarger or table, the flatness of the negative during printing, the easel being used and is it holding the paper flat. After all those variables are controlled you could evaluate various papers keeping in mind that apparent sharpness is more important than LPM and needs to be evaluated with regard to the size of the print and the viewing distance.

Finally, you may find that your favorite paper may resolve less then other papers, but those papers produce inferior tonality or range for your application. If you are working with 4x5 and larger, you may want to explore unsharp masking techniques which do not actually produce a sharper image but do produce more apparent sharpness through control of local "micro"
contrast.

And of course one can eliminate several of the variables by contact printing.