Well, let me start by saying this - it may not apply to you specifically but I'll say it for the benefit of other readers who may need additional info:
Most of the time, the "steep learning curve" and "ease of use" issues with notation software are because people don't know how to notate music without software!
"The Best" IMHO, despite it's many irritating elements, is Finale. It does everything you'd ever need it to do.
For a long time, it was the only "professional" game in town. However, Sibelius came out about a decade later at a much lower price and touted a "not as steep learning curve". You used to very commonly see comments like "Finale is great but it has a really steep learning curve". But to be honest, I saw nothing about Sibelius at the time that made it any less difficult to learn (and it had its own irritating issues).
The one good thing that came of it is now that Finale had competition, they had to lower their price to compete, and both have been in sort of a "features race" and also it forced the makers of Finale to actually listen to what users wanted and implement the features rather than just writing the program the way they wanted.
I still prefer Finale. But we have Sibelius at our university and I've kind of been forced to learn it. The biggest thing I hate about Sibelius is the look of the program (which was apparently redone right as we got it) - it looks like Playskool or Little Tikes. "My First Notation Program". In fact, a lot of people complained about that.
But I do see what they're going for - a logical typical working order.
The other thing that drives me crazy is the little window with your tools on it is not resizable. This alone is a deal-breaker if I were to be choosing between the two.
However, their idea, not unlike Pro Tools (which are now both owned by the same company) is that you use keyboard shortcuts for most of your work. So if you know your numeric keypad (and still actually have one on your keyboard!) you don't really need to be able to see that window so well.
The guys who original made Sibelius got hired by Steinberg to make a notation software they could market and maybe compete at the level of Fin and Sib.
It's called Dorico.
I think it's a joke at this point. They rolled it out at a very similar price to the others with, oh, I don't know, about 1/10th the features. There seem to be a lot of fanbois who are really the type who like Dorico because it's not "the other two" and because it's "not Avid" (or whoever now, probably Behringer or something) or just because they hate Apple and Microsoft and want to use Linux, they carry that same mentality over to Dorico.
The default font is actually too bold, and goes the wrong way for published music, but hey, I'm just comparing things to engraved scores...
I think there's also some fanboy support for other things - including Musescore, Notion, etc.
There are some out there that still use more of a "command line" input to create music. Talk about unintuitive!
At any rate, it also depends on what kinds of features you need.
Do you need Guitar Chord Diagrams?
Do you need Tablature?
Are you interested in scoring for other instruments or just Guitar?
Do you need it to look like professionally engraved published music, or is a quick and dirty lead sheet good enough?
Many programs don't even put in the right accidentals when you put in a scale - hell, I've seen some that use flats only!
So there are a number of factors to consider. Finale will do anything you could ever want. So could Sibelius. Your choice of one or the other might depend on which company you hate the least, or whether or not your collaborating with others who use on or the other. While I still prefer Finale, if I was able to buy something new I'd switch to Sibelius for practical reasons just because that's what we use at my work. I could make files at home and email them to myself rather than having to stay in my office extra time to get it done.
But, because they can do so much, they are sort of necessarily complex (and so is the art and craft of notating music BTW). So the real trick is wading through the unnecessary stuff and learning the core stuff you need to know.
And I should add, that really, I think a lot of people buy software like this thinking they're going to input their music in a day by clicking in the notes and have it come out looking perfect.
In a sense, you have to "practice" Finale or Sibelius - learn the program as you use it. It's kind of like the kids who download a free DAW and expect to make their #1 hit Rap record. Then they're on a forum the next day asking about NY compression and "how do I create a track"... (in case you don't know, the latter is a basic that you have to know long before you start messing with compression).
So you need to learn how to set up a score. Then you need to learn how to enter notes and rests. Then you need to learn how to put in ties, and space the music, and stuff like that.
I think some people want to start in measure 1 and perfect that before they go to measure 2 and that's not how you do it (and Sibelius' is designed in the way you should work which is kind of nice).
But also, people want to just make a perfect piece the first time they use it. That's not going to happen either.
You need to do some "demos" first and learn while you do them.
Classical Guitar music often uses multiple voices which is sort of an "advanced" use of the software so you kind of have to learn to do basic monophonic, then block chord work first, before moving on to multiple voices. Workflows can vary, but none of them are going to be "easy" because of the complexities of music notation itself.
If you're "serious" I'd go with Finale or Sibelius.
If you're just a "hobbyist" but can afford it, go with Finale or Sibelius.
I can't speak to Dorico, Musescore, Lilypond, Notion, Encore, or others, but some are PC only, which I don't prefer, some are "command line" entry, which a lot of people don't dig (but some gravitate to it) and others just either don't have quality output, lack features you may want, or lack features that anyone in their right mind should have.
First decide if you need tab and chords, as that will eliminate some.
Then decide if you want click on screen and/or controller keyboard note entry as some may not do one or the other.
Decide if you want playback so you can hear what you notate - some of them have better sounds than others, some don't offer the feature within the program.
You may be able to get by with something less feature laden than the big boys, and some lesser priced ones might be just as feature laden (if not as intuitive).
I tried Notion once long ago and found it lacking, and I tried Musescore once and found it unacceptable. But I'm doing lots of various kinds of things where I need traditional orchestral stuff, modern pop stuff, and things with tabs, etc. So I needed more versatility than some of the others offered for me. I've got a really old version of Finale and it still does absolutely most of what I need it to do. The newer versions really haven't improved much on the notation itself - more on the audio features than anything.