Problem number one, is that apparently it's not fun for you.
If you sit and think that "this" has to be perfect, and "that" has to be perfect, then you're just sitting there with a bunch of problems.
Not even the best place on Earth, or not even the perfect woman, is perfect.
The important thing, is that it's fun for you.
If you have a clear vision, and you sit down to work towards it, it will be tons of fun.
If you lack the technical skills and mapping experience, it will be difficult, and the fun might begin to slip away.
Everybody can envision something within their scope of talent or mapping experience. So, all that remains is to work towards it.
I've had a project in the works since 2009. It's still only 40% complete. It came to a halt, and mapping has for about 80% of its life, has been unfocused - I was just sitting by the map editor, mapping nonsense - I was actually just wasting time, because there was no focus.
I signed up for another project, as a fun side-mission for myself. I started on something, and found myself in the same path as my original project - mapping was meaningless, and the progress I made, didn't have much focus behind it.
I scrapped what I started, and decided to FIND something interesting and fun, to get me excited. I did (pink sky, Halo 1-like landscapes and buildings), and the progress went through the roof.
---> It's not perfect, but it's the best that _I_ can do. <---
you will need to accept that as a fact, and do your best from there.
It's okay to WANT to be able to make a map like how the GothicDM team did back then, but it's not realistic.
Do your own thing, and be satisfied with it.
If you give up, then it's possibly not just with mapping that you give up. If it is, the maybe you need more experience -- which can't be rushed, either...
In any case.. good luck :) and have fun :DDDDDDDDDDDDDDDDDDD :((((( :ooooooooo :)