The E190 holds roughly 13000 kgs of fuel, and burns roughly 950 Kgs a side in cruise. The aircraft in operation has no problem filling full fuel with a full passenger/cargo load. The longest flight we presently fly is YYZ
, 2100 miles. That would be the maximum theoretical range of the aircraft, as full fuel is loaded.
So, if you mated the E190 wing to a E175 fuselage, there would be no change ... full fuel again. Perhaps a bit longer range, if the aircraft weighed less.
Now, the E175 burns about 800 kgs a side in cruise. But that is at E175 weights. The E175 at roughly 38000 kgs is 13000 kgs lighter than the E190. There is a very good chance that at the higher weights, the smaller E175 engines would burn just as much fuel, as just as much energy has to be produced.
The only way a longer range can be produced is if fuel tankage is increased, filling more of the wing ... or introducing a centre fuel tank system. But remember, on a trans-con flight fuel burn increases at a rate of 17%. In other words, it takes 170 kgs to carry every 1000 kg increase in fuel.
Just because I stopped arguing, doesn't mean I think you are right. It just means I gave up!