I've spent the last month or so playing every guitar I can get my hands on. I was encouraged to do so by my partner after visiting Andy Manson, who built her main gigging guitar. Julie, who sings the praises of Andy at every opportunity, had been trying to persuade me to order an instrument from Andy. Problem is, as soon as he started asking me what I wanted from a guitar, I realised that I didn't have a clue!
I have been amazed at how important the thickness of the neck is to me. Sure, the width of the neck is important, Sure, the action is important, along with the string weight and scale length. I just hadn't considered the thickness of the neck before. I now realise that I find a shallow neck, with what I can only descibe as a "flattened D" shape to the back of the neck, really makes a guitar sit well in my left hand.
I now have a much better idea of what I need from a guitar for it to be "playable". Others will have a different wishlist, which is why there are no stock answers to the question.
I also have the advantage of a partner who runs regular guitar workshops across the UK, which gives me access to instant advice on my playing posture, hand position etc (OK, I admit it, she nags me!) so once I have my perfect guitar .... I'll have no excuses.