There are very few upgrades that will increase your MPG.I know you say you drive the same, but did you ever get on the gas just to see what its got? Just one hard acceleration or passing someone will eat your mpg. Is the gearing the same? Also use your gps on your phone or nav to make sure you are going the speed your dash displays.
The only real “upgrade” you can do to improve MPG is lighter rims/tires. Might google the weight difference between what it has on it vs what you had on your old ride. I just bought new tires on my truck that are 15 lbs lighter each, than the old ones, and I gained 4mpg. Just depends on who you want to pay, rim company or gas company. Also the sooner you buy lighter rims, the more money you will get back from them if you go this route.
Number 1 thing to improve you’re Avg MPG is let off the gas sooner when slowing down for a turn or stop. When not in heavy traffic, the more you coast the more miles you get per gallon esp exiting the freeway. Give people in front of you more room so you are not breaking every time they are, instead just letting off the gas and coasting until they are done texting and resume the speed limit.
Number 2 is lighter acceleration, you can watch your instant mpg and see how much peddle to use to get your best mpg. There are also spot where you can let off the gas and it will switch gears sooner, which should get you better mpg. Getting up to speed faster does not save you gas, you can’t get back gas you burned. Find your peak hp/torque and try to keep your rpms there when accelerating.
Using Cruise control can help a lot too, Some people might tell you they can get better mpg in hillier area’s than using CC, which is generally true, but you should also be able to change your CC accelerations aggression level which will keep it from doing hard accelerations up hills. Hopefully soon they will put in an angle parameter into the CC calculation.