With an electronic tuner, putting new strings (Newtones 10-47) on my Guild G212 takes about 30 minutes from start to finish.

I find I tune it up to just ABOVE concert (wind the octave G SLOoowly) and let it settle for about an hour on its stand.

Go back and tune to concert, you'll often find that it's settled below concert pitch as the guitar and strings get to know each other.

After that, I'm fat, dumb and happy.

I used to finger pick my EKO Ranger in the 60s, but can't get a sound I like out of the Guild, so I use a soft flatpick.

The nut width is the same as my Martins and feels a bit crowded down there - however, persevere and it'll get sorted.