Just went back and read the entire thread and realized there are 2 camps here. I think repairing an item yourself or taking it to LV (or whichever brand manufacturer) is truly a matter of what you're comfortable with. Very few people are storing their items in a controlled environment so over time leather is going to age and weather of its own volition. If you don't care for it it could start to become brittle/tough, no longer supple like a baby's bottom. I have a lovely Chanel wallet in the lambskin that I had to stop carrying because the leather seemed so delicate and the hardware was starting to tarnish. Drove me nuts that that was happening to such a high end piece versus the vintage handbags I have from the 30s/40s that are in perfect condition.
In the case of the LV Epi wallet and the lining I'm looking to fix, I've read that others have taken their items with the Vuittonite lining back to LV for repair and were told it was a 'feature not a bug' and the item would not be repaired. So, due to the fact there's no LV store that I'm willing to drive to, I'll try and repair myself. Especially when no one will see the lining except me, and frankly I'd rather look at a solid color than a peeling lining.