Sorry a bit lost here -
organize and
workplace just do not go together in my life

As for chairs, if I had the money and space I would buy one of these without hesitation:

BUT as the need is for a desk chair I have used two chairs for the majority of the last 20 years and they have helped my bad back (odd shaped joint / bone) control any aches and pains.
This one rocks to allow you to lean forward when you are working and then sit up straight again to use the computer:

The drawback is that it can be hard to get under the desk and slide forward / back as needed. It is key that you
do not put pressure on your knees - you weight MUST reside on your bum. You also have to cover the seat and get new foam after 10 years or so!
At work (where I sit most of the day) I use:

As I slide in and out and around a fair bit the toes of my shoes can get scuffed or pick up the carpet colour but new shoes are cheap compared to a chiropractic session (or 6 as was normal)
Neither chair was cheap and if you have not tried one before the back does hurt after the first few days till it gets into being in the correct shape...
A few hints I have that worked for me:
1) Do not twist at all (hence the swivel version)
2) Get up and walk (even to the kitchen for tea) frequently and often.
3) Have the desk at the correct hight for the chair (or vice versa) - do not lean forward
4) If you have a computer on the desk raise the monitor so the top is level with your hairline or eyebrows
5) Keep fit - swimming is great for the back and the breathing
Ok - so I only manage 4 out of the 5

It is worth taking professional advice and if you are in the UK we have used
Shape Seating for these chairs. Even our dining chairs came from here and really give visitors a shock as they rock...
Final bit of help - do not skimp on the money. You only have one back and they do not mend very well or quickly.
Hope this helps a bit
Andrew