I've read both this thread and your original one and hope you don't mind me saying this: you're doing something that I'm often guilty of myself: overthinking, in a big way. We could continue this discussion for months, and at the end of it you will know no more about YOUR preferences for sound and feel than you do now.
The all-mahogany might be satisfactory for a one-and-only. It might not. You might love a 1.75" nut. You might prefer 1-11/16, or 1-23/32, or 1-13/16. You might find a v-neck uncomfortable, or it might be perfect for you. You might be comfortable with a 25.4" scale, or you might find the lower string tension of a short scale easier. You might like a Larrivee, or you might find that you prefer the sound of a Martin.
The only way you will ever find out what your preferences are is to play guitar. You can solicit advice from strangers on the internet for years, but we can't tell you what your hands and ears will prefer any more than we can pick your favorite ice cream flavor for you.
My suggestion at this point: just buy a guitar. Whatever you think, right now, that you'll like most. You've done a lot of research and have some good candidates. If you really think the sound of the all-mahogany is too limiting for what you want to do, get a spruce top. If you're just repeating what you've heard others say about all-mahogany guitars being specialized, then I'd say you need to trust your own ears and get the 000-15.
They don't know what you like. If you're not comfortable spending that much when you aren't sure what you want, buy something inexpensive - with the understanding that once you get to a point where you can play a bit, you'll go to some stores and really audition guitars.
Then, after you've been playing for a year or two, if you find that there's something about your guitar, whether it's a 000-15SM or something else, that annoys you - whether it's sound or feel - you'll be in a great position to go and audition a wide range of guitars and find what you really love. Or maybe that won't happen, and you'll be comfortable with the guitar you have and enjoying making music and not be bothered about whether something else out there might be "better."
Just my 2 cents, and probably worth what you paid for it.
