I picked up a New 629-6 4" model a couple of months ago, and have found it to be my 'Favorite Shooter'. I like the way it handles, and it seems to be just the right weight and feel for my liking.

What would be some of the minor upgrades that I could do to my revolver to make it 'Mine'?

A friend mentioned maybe a Cylinder & Slide Extended Firing pin since I fire reloads a lot, and a Woolf Gunsprings Spring kit.

What are your thoughts?

If it ain't broke, don't fix it!

What gboling said. It's not a Mattel toy or a Barbie doll. Historically, S&W revolvers (and autos too, for that matter) have been sold complete. They don't sell it with a "B" grade cylinder that you can replace with an "A" grade cylinder when you want to spend more money. About the only place for improvement used to be grips, but they have recently improved even some of those, and it sounds like you like the ones you have now.

How about a set of custom Kurac or Keith Brown grips? They are both incredible artisans.

I am squirreling cash little by little for a set of coco bolo or walnut Kurac grips for my 28-2.

In terms of messing around with the internals, if it is a good shooter now, don't mess with it, just for the sake of personalizing it.

Keep shooting it, and see if there are any short comings with your groups that would necessitate a change.

To me, a Smith Revolver is the antithesis of a 1911. It doesn't need a lot of customization.

Ad a side note, I love 1911s and have a real nice Kimber that I have had some custom work done on.