Easier said than done, of course, but...
I had traveled for a few years before I started hiking. Much of the knowledge (travel light, the layering method, synthetics, etc.) crosses over seamlessly. But I found out that what's "light enough" for walking a mile between train station and hotel is completely different when hiking up steep inclines for hours! My "Big Four" (tent, bag, pad and pack) were all pretty light -- and at first I felt good about saving a couple of hundreds of dollars by not going ultra light.
After two hikes, I swapped out almost everything. Thanks to REI's no-hassle returns and Ebay -- I was able to get most of my money back.
The mantra now is "buy the lightest that will do the job". No fun being a mountain mule.