As for your statement, "Extremely pricey", I only have to say you get what you pay for. I have a "Range" devise that eliminates V4 mode and it is a simple plug in item and no threat to warranty. But that only took care of V4 mode. You can also pull gear selector down and select D4 or D5 and that will eliminate V4 mode and give a slightly better shift response. That does nothing for engine performance.
You can also buy a plug in tuner that has 3 select "canned" tunes for the vehicle. Not much help if you put some add on's but again an improvement over stock many say.
I myself chose to do a custom tun from Black Bear Performance after much reading and learning. They have different tweaks that really help transmission shifts and if you ever add on performance parts, they will adjust the tune for that mod. The trans was my main issue but I can say I did feel a bump in performance... I do NOT have a heavy foot.
It all depends on what you want in the long run. If you are going to be in the truck for some time I would consider getting a tune that can be modified with future add on's, but that is JMO. Good Luck