I go cheap on lots of my hiking clothes (Columbia shirts for example), but I tend to watch for sales and buy the more expensive pants. I like schoeller dryskin - very tough material- designed for climbing so it is heavier than most backpack pants but they last forever. I found some Arcteryx light nylon pants on sale at REI and then use fleece longjohns to add warmth when needed. With the schoeller pants I do not take long johns. So with the extra weight of long johns I have not really saved weight, but have added to the versitality of the clothing system. You can get by with part cotten in some areas, but I strictly stay away from ANY cotton when in wet-cold conditions. I have done lots of hiking in wool pants too. This is pretty "old school" nowadays. Men's light dress wool pants are great and I can pick them up at Goodwill for a few dollars. Some people do not like the feel of wool. Also in the "old days" standard hiking system was to wear nylon shorts over wool long johns. I actually like that system although it looks really funny. I am also a big fan of gaiters. I often wear long gaiters with hiking shorts, leaving my knees free yet protecting me from getting wet with dew. Different slothing may be appropriate for different climates and conditions. Where and what temperatures and moisture do you anticipate?