I used to drive tractor/trailor (O/O) and switched to a straight truck. You might want to drive for someone to see if you will like this. The money is a little different. Alot of it is the same as far as dispatchers, picking up and delivering etc..
Unless you have alot of money, don't buy a new truck. I did and its been tight. Some days I wish I would of stayed with tractor/trailor but sure is nice to be able to turn around quickly instead of driving 5 miles to find a big enough place for this big rig. Its nice to be able to pull into burgerking or walmart. Can't do that in a big rig (usually got chased out). I do miss my big sleeper though. I made the mistake of getting a real small sleeper on my FL 70. Hope it works out for you. Good luck.
Safe driving
Randy