Does 23-25 MPG for a 2.4 sound about right?

My 1996 has the 2.4 with 5 speed. I do a 50/50 mix of freeway and city driving. I do not tow or haul anything in my bed. It has a shell on it. I also drive like an adult. I noticed when I first change the oil to Mobil One high mileage I get 25 MPG. Then a couple thousand miles into driving the mileage slips and I start to get 23 MPG. Does this sound like good, bad, or average mileage for a Tacoma with 180,000 miles on it?

Also, car has always shook very hard when it idles cold. I cleaned MAF, throttle body, put in new wires, cap, rotor, and stock Denso copper plugs. STILL shakes (and I mean SHAKES) when I take it out of gear and idle. What could be the cause of this? When it warms up, runs smooth. I thought fresh plugs and dist cap would fix the shakes

 

Trying posting in the 1st gen forum. my guess is check for codes first then try a fuel injector cleaner