JohnnyLongpants

The answer is yes, almost certainly. The question, however, is quite vague. For anyone to answer regarding a specific situation or application, more details are needed.

Buy some masking tape. That is the solution to all leather stretching problems, because paper tape does not appreciably stretch. Stick the tape to the back of your leather. Then lay down your straight edge and use whatever blade you prefer, so long as it is sharp. The masking tape is also useful if you get into tooling or carving leather, as both of those processes distort the shape of the leather. Having tape on the back keeps this from occurring.

Except that I have actually used it, and know people who use it on a daily basis to remove stains from leather. I might suggest relying on that experience over the experience of a random Amazon user. Even if it does fade the area surrounding the ink, there are solutions for that. If the idea is to get the ink out, Angelus Spot Remover is among the best on the market.

In general, you want there to be a degree of proportion between the stitching and the project. Having a very thin project with very large stitches can (emphasis CAN, not saying it WILL) look out of place. For 5 mm stitching I use 0.8mm thread (or, in Maine Thread, 0.030"). I agree that this stitch spacing is pretty large. I would minimally move to 4mm stitch spacing, at which point I would use 0.6mm thread and needles that were about a size 3, but could be 1 or 2. I use Osborne harness needles mostly because they are so available. -Johnny Longpants

A quick coating of CMC (carboxymethylcellulose) is a nice approach. It's not a hardcore protective finish but does make a product display- or sale-ready. Horween leather--in nearly all cases--is sold finished. From there it's the question of using the right leather for your purpose. If it's a pull-up leather, there is not a ton you can do. You can put thin leather along the seam and "bind" the edges. If you don't like Resolene then maybe you can tell us which products you like to work with and we can help from there. If I was out of Resolene I might just go with a nice beeswax edge finish, topped with a little shoe polish to give the edges a nice satin sheen. Then I use Resolene but I don't know you don't prefer that.

Angelus Spot Remover. Other companies make it as well. It is made specifically for helping with leather or suede. A small bottle should be under $5.

Acrylic paint that gets wiped away after applying, as if it was and antique finish. Typically, you apply the product, then do something like wrap a paper towel around a ruler and wipe off any excess up on the surface of the leather.

Spray starch--the same stuff dry cleaners use on shirts to make them crisp. There are other specialty products but this is as easy and easily-available as anything else.