I've daily driven my YJ for the past 8 or 10 years with both front and rear axles welded. You can only do the front if you have a CAD (central axle disconnect) axle. If no CAD you will need an automatic locker like the Aussie or LockRight.
Welded axles aren't for everyone. The welded rear will take a little getting used to in snowy or icy conditions. The traction is great but a little blip of the throttle in a turn will turn you sideways if on a slick surface. I love it for this reason but you have to know what you're doing.
A welded front with CAD is great if you can set up the CAD with a manual disconnect like a cable. I used a vacuum switch from a full-size Jeep with Quadratrac, then I can disconnect the front and run 3wd for better turning when offroad. Poor man's selectable locker of sorts.
Now that I've upgraded my axles to Dana 44's, I run spools in both axles. THe front d44 has a cable actuated disconnect and locking hubs.