I always suggest trying to rent and shoot as many guns as possible prior to purchasing. If you rent some of those, you may find some that you absolutely love, and others that just don't do it for you. You may find one that you like even more than your Walther. Think of what the most important features and characteristics are to you, and then make a list. Some of those are striker fired, some are DA/SA, some have decockers, and some have decockers and safeties. Some are single-stack (Sigs) and some are double. Are you planning on concealing it? The only two on your list I have experience with are the USPc 9mm (my daily carry gun) and the XD9sc. They're both excellent weapons, and I've really only heard excellent comments on the others you have listed as well. So yeah, rent as many as you can and, in the end, get what makes you feel the best. If that's a second Walther, awesome!! The only thing better than one gun is two guns...or 3, 4, 5...
ETA: Forgot to say, keep in mind that range guns will have several hundred or thousands of rounds through them, so they will be very well broken in, and the trigger will have probably smoothed out a lot.