palm reinforcement

Maybe use silicone, or silicone diluted with mineral spirits, or polyurethane like McNett Seam Grip. I've done that with leather, but likely wouldn't work with fleece, but you could try it on a piece of fleece.

If you're making the gloves and they're easy and the fabric is cheap, maybe don't worry about it?

The stretch nylon/lycra used in backpack pockets should work. It may not be much, if any, lighter but seems abrasion resistant and durable.

You guys are fast! The purchased fleece gloves I have had silicone buttons on the palms, and they have peeled off with just using them for driving, never mind using hiking poles. The lycra's an interesting idea, I have lycra fabric that I was using for binding. Not the same as the fabric on the backpacks, of course, I'm not sure where I'd find that. But then, I'm guessing the gloves won't last long anyway, I just have extra fabric from my vest that I'm messing around with.