There are some improvements you can do for little to a lot of money. The seat of the pants analysis will tell you that there were some gains, but really, without significant changes to the driveline or weight of your Jeep, your power to weight ratio is minimal and you may or may not like the results. My TJ weighs 3780#s with a 1/2 tank of gas. That is pretty heavy for a 120hp engine that could when it was new. Best thing to consider, figure the gear ratio to the tire size you will be running. Stock, depending on tire and trans, 27-28" tall tire with a 4.10 or 3.73 gear ratio. If you want a little more pep, get a gear ratio that is slightly deeper (higher numerically) to get you into the higher rpm range quicker. Your 4cyl like to rev and at highway speeds, it should be over 3000-3100rpms.
If you like being around people with the same interests, look for a local 4wd or Jeep club. Comraderie is fun, you gain knowledge of your Jeep, you'll learn offroading techniques, and you'll have a whole new set of friends. Some people are not into clubs and that just as fine. Some clubs, you don't have to participate in everything they do. The club usually functions for the majority of its members.