"Journyman" is a skilled craftsman that can work with out supervision.
Depending on what part of the country you are in the next step up is Master.
For Master in some states you need to take a state presented test that will licensen you to operate your own buisness.
Thats not really necessary for welders though, thats mainly Electrical, Plumbing Heating and Air conditioning. How ever if you have a masters license you can hire Journymen to work for you.
In some industrys the person incharge of all Craftsman and there supervisors is called a Master Mechanic some call them General Forman or Superentendent.
If you can get in the Union and get the training you will never regret it.
I am not promoting Unions just the formal training they can provide. Years ago companys use to offer apprentiships but now days offer very little in the way of training.
The Union is not a blood oath type thing, you are not bound for life should you not like it.
As a Union hand you are confined to the negotiated wages no manner how good of a hand you are.
Another bad thing about the Unions is they can sometimes be just like the Executives at Enron, World com and a few others. But at least you get vote on who is gonna rob you in the Union.
If you want to move beyond an hourly wage earner you can withdraw from the Union or just quit. In some constuction Unions you can with draw and keep some of the benifits.
Power plants usually have out standing training programs (The ones I worked in did any way)
Travel is another like or dislike issue not a must. My wife and kids loved traveling with me from coast to coast.
Now my advise! Take the job that stands to net the best pay right away and get your #@&^%* back in school! Get a "Welding Engineers" degree or something like it. There are no limits to the field of welding, only the ones you impose upon your self.
You maybe industructable today but today slips away before you know it. You need to know alot more than just how to lay down a good weld in this day and age.
I have 3 daughters and they all can weld pretty good, but not for a living.