Welcome to head-fi and sorry about your wallet
Found this picture:
Test comparatif ATH-A900 vs AKG K701 | Blog Casque : du bon son dans ses oreilles But for some reason A700 feels bigger than k701 on my head. HD595 feels lighter, smaller and looks more natural on my head. A700 is comfy enough though, size wouldn't be a problem for home use.
A700 will sound fine for your music and decent for acoustic guitar, not the best but decent.
I like HD595 sound better than A700 although it has less bass. It produces better vocals and has a little bit more soundstage. I have a preference for open headphones' sound. However, I believe A700 is cheaper and matches your music better, go for it.
Some people tried the D1000 and Q40 and seem to like it, have you considered them?