Sounds like you are well on your way to evolving to a gear list that works for you.

For discounted clothing, Sierra Trading Post. I recently bought $300 worth of clothing for $100. They have discontinued items and seconds, but all very servicable. My suggestion is to pick up a synthetic base layer from there or Walmart or a thrift store. You'll need at least one other pair of socks so you can switch off while the other one is drying, either after a wash or a creek crossing. You can use any synthetic athletic pants and shirt to hike in. I generally have a tee, a fleece, a windshirt and a poncho. All can be worn at once, or if it's just chilly the windshirt and the tee, or if it's drizzling rain and warm I throw on the poncho over everything. As long as it's not a wind driven storm this keeps me dry. The base layer is my pajamas. My pants are nylon zipoffs I got off the clearance rack at REI. Hiking in a rain shell meant I was soaking wet from my own sweat; the poncho is a better solution for me when I'm not in a wild storm. Anything more than a windless rain and I'm setting up camp to ride it out.

There's a simple aluminum pot at REI for thirteen bucks - a lid, a bail handle, and wide enough to be stable. An IMUSA grease pot from Walmart or the Kmart grease pot would be about five bucks.

If the insole in the boots looks flattened or worn, you could get a pair of Superfeet in the appropriate color to augment or replace them. They aren't cheap but they are more durable than the stock insoles. It seems boot makers expect you to replace the insoles.... Talk to someone at the store where you got the boots.

I hope the REI Flash works out for you. The straps and belt did not seem to me to have much padding. Keeping the load as light as possible will help.

You can get 2mm painters cloth and cut the plastic to fit the floor of the tent, then trim it just a bit smaller. If the edges do not extend beyond the tent it will not become a water trap like jimshaw thinks. Site selection is much, much more important in a tent than in a hammock, so look for flat spots that aren't going to collect water if a rainstorm blows in.