Number one looks the most comfortable and I think I see something pink on the wall in your bedroom that would relate to the pink chair. With space being at a premium, why not replace the sofa with something more comfortable?

If you're already putting all the effort and money into making changes for something more comfortable, why not just replace the couch with something much more comfortable? Then you can still put a tall plant in that corner where you would put the chair. Otherwise, I like #4 the best for comfort.

They all could be comfortable or not, hard to say without sitting in them. I have a MCM chair I got from a friend when she was cleaning out her mom's place, and it looks uncomfortable but everyone who has ever sat in it has told me they were surprised at how comfortable it was. And a lot depends on the dimensions of the person sitting in the chair too. My dad's lounge chair looks super comfortable but it is not.

What about the IKEA strandmon? It’s quite comfortable, tall, not too big, and comes in yellow and light turquoise:

With all due honesty, I had lots of comfy chairs in my last home where I lived alone, and almost never sat in them. I hung out on the couch and the only folks who sat other places were guests or me when I had guests. I agree with some other posters, spend your money on a kick butt couch, or even a high end futon. They also make futon chairs which can double for sleeping over guest if they are young enough to be able to get off the floor, lol! Whatever kind of seating I chose, I would make sure it could do double duty for some purpose I needed. However, I could be wrong, maybe you'll sit and sit in the new reading nook. The only chair I ever would sit in occasionally was my rocking chair, different vibe from the couch.