Howdy Bleverman:
Welcome to the forum. You didn't say what year, what trans or what car your 144 is in. Also do you want to keep it stock appearing? In anycase, start with a good basic tune-up which includes a finding and stopping any leaks, gas, water or vacuum, a good carb cleaning, an ignition tune-up and adjust the valves.
You can easily go a carb upgrade by bolting on a carb specified for a 170 Falcon. If you have a '60 - '62 144 it will have a 130 cfm Holley side bowl. Moving up to a 170 carb will increase cfm to 150 If your's is a '63 - '64 144 it will have an Autolite 1100 also rated at 130. The 1100 from a 170 is rated at 150 cfm. Make sure your carb linkage is giving you wide open throttle. Learn to adjust your low speed air screw with a vacuum guage.
You're limited in your distributor upgrade options, but I believe Petronix Ignitors are available for your engine. It will give a stronger, more consistant spark and allow you to use a wider spark plug gap, a cooler heat range spark plug. As always, use as much initial advance as your circumstances will allow.
IF yours is a '60 to '62 144 you have the old, prone to cracking exhaust manifold. It has a 1.75" outlet and a flat gasket connecting it to the head pipe. Upgrading to a '65 and later exhaust manifold, which has a 2" outlet, and a 2" exhaust system with a turbo type muffler. This will be a good foundation for later improvements.
As with any six cylinder upgrade, know that lighter is better. So don't haul around anything that you don't use daily- except for your spare tire, jack and tire wrench. Be sure to air up your tires to the max stated on the side walls.
Hope that is what you are looking for. All of the above suggestions will maintain a stock appearance. Very few will be able to spot the differences. Assuming that your engine is in good shape, the above upgrades should equate to about a 10% increase in power and performance.
Adios, David