Here are my top modifications that I have found to make my Powertig 250EX a real joy to use.
The best mod I found was to replace the original factory torch with a 20 series torch. I chose the Weldtech WT20F-25 watercooled torch. It is a 200 amp torch and I love it. Bendable head and really light and easy to handle.
The next best mod I found was getting a larger argon tank. I started off with a 125, then a 150, then a 200 and now a 325. Not having to go to the LWS every week is great plus the price of gas goes down with the larger tanks.
Next best mod was getting a longer ground cable. I now have a 25 foot cable and it makes for easier welding in a larger area. Instead of dragging the cart around, I can move in a 25 foot arc around the welder. Plenty for what I do.
My plans are for a new foot pedal, although the factory pedal is fine. I hear some good things about the foot pedal offered by Everlast.
I also plan on getting an Everlast water cooler. I hate having to drag out the hose every time I need to weld. Having that hose just makes for more things to have to watch not to trip over.
I've got to say that having the Powertig 250EX is a joy. I now wish I would have gotten it sooner. Being able to make things that others only dream about is what it is all about.