I don't have any answers for you, but I am watching what others post - as (someday - I've been saying this for a looooong time) I hope to own an embroidery machine.
Hand sewing??? Wow!!! I can't wait to see what you make!
I do have pictures of my sewing room on the internet, somewhere... And if you belong to Facebook, there is a Disboutiquer FB page, where all of us have all of our sewing rooms posted. When DH was building my sewing room... I found a lot of ideas on Flickr.com - there is a sewing room group that has THOUSANDS of pictures... so just go there and do a search - it kept me busy for days.
For my sewing room... I use office chairs. I have one and dd has one. I don't get any back pain from those, like I did when I was sewing on my dining room chairs.
A lot of people recommend using Ikea storage systems for their fabric - I just use a regular shelf, but what ever you choose, I am sure it will be fine.
DH put regular counter tops into my sewing room - and I love them - they work perfectly. He drilled holes intermittantlly, so I could run my cords behind my machines - I really couldn't be more thrilled with my space, and very thankful that I have a space.
Here's one overall view of my space... I don't want to share too many pics, because I've posted them here a few times, and I really need to take some new ones, since I don't use any of these machines anymore (except my serger - rarely)... And my space is VERY small...
IF you are interested in seeing more detailed photos of my space, I have a post in my PTR devoted to it...
http://www.disboards.com/showpost.php?p=43050928&postcount=592
The thing I recommend the most, is to really tailor your space to fit your needs... Most of the time, I sew small items, so I can get by with a smaller space and cutting area. But I know, for a fact, if I was constantly cutting larger items, my cutting mat and the way it's situated (only accessable from one side) would be an issue. I've been able to adapt though - so that is good. Make it a space that YOU enjoy being in - light and fun colors are always best - it's easier to see... and GOOD LIGHTING is a must.
Have fun, and please show us pictures when you are done.
D~