anytime someone asks "how hard is _____?" it is always relative... changing out CV axles to me is one of the most straightforward things I do on my rig (Primarily because I have them in and out so many damn times at this point..)
Condition of your rig also plays a major roll... some things that are a breeze on mine (no rust, original florida car) end up being a 3 hour bolt removal process on some norther rigs.
All in all, great advice in here... I definitely second replacing the seals.. I was lazy and left mine alone last time, quickly discovered a leak soon after, and guess what? Literally had to the job all over again 2 weeks later
Worst thing for me seems to be popping the axles/c-clips back in.. you need to make sure they are sitting on the top and not swung down and drooping, but even with that I have an axle that just doesn't want to pop in and since I'm lazy and do the work myself it becomes a crappy process of struggling to seat it properly without tearing the boots or the seals.
I'm not running the front sway bar so that for me is out of the way already, but literally the only bolts I remove when swapping axles are the 2 lower balljoint bracket bolts and the axle nut (obviously). I leave everything else in place and just manhandle (or use a floorjack) to raise the knuckle where it needs to be to get the axle out, and viola!