I heard that Gimp was freeware that worked just like Photoshop and just as well, but I never could figure the damn thing out. I got Photoshop Elements with a new camera years ago; but I didn't get very sophisticated with that, either.
There was a time when Lightroom was free, and I had reasonably good results with it; but not good enough results to want me to pay a hundred bucks once they started charging for it.
So, I've been using Microsoft Office Picture Manager, which has some modest tools for tweaking and cropping and adjusting and such. I have tools for adjusting color; but I haven't been able to get the sky to "pop" on a lot of photos, and it just turns out white or monotone grey instead of the pretty color it had in nature.
Take a look at my latest trip. You'll see that I WAS able to get the color to "pop" on a good number of photos, usually without adjustment. If you take photos in the golden hours of early morning and late afternoon, the colors can be wonderful.
I just bought three filters to supplement the UV filter I already had. I'm looking forward to experimenting with them.
-Joe-

The Colorado Plateau (click)