You can add a gusset to the groin for better flexibility and wear resistance, it’s much better for workwear and you’ll see it in a lot of martial arts pants as well.

Besides that I recently was reminded that damp cloth abrases more, and it might be pertinent to switch between multiple pairs of work pants over the week (give each a couple days to air out inbetween). Apparently this is where the 5 suits recommendation is from, although for wool suits.