It's an interesting question, before I started my transition I could not care less about my look and I thought about my body more as something to walk my brain from one place to the next, as a consequence I didn't take very good care of myself. I think this was partially due to not really caring that much if I lived or died, not really suicidal since my teenage years but never afraid of taking risks.
After I started my transition I started taking pride in my body and taking care of it, when I came out to some of my gay friends as trans they somehow felt like they could share what they thought I looked like before and how they were sad since they thought I was good looking, I wasn't exactly sure what to say to that and since then I've had gay men try to persuade me that I'd be a much better looking boy, still not sure how to respond to those comments but what I do know is that I don't really care what I looked like before.
Today I like to look pretty and go out on the weekends, for work I dress more plainly and wear way less make-up both because I can't be bothered with the full routine and because it's a professional setting.
I realize the following might sound a bit shallow but I'm being as honest as I can with myself and others. I don't think being pretty is required for me but I like to present myself as well as I can and I like it when other people find me attractive.
If presented with the choice of transitioning without any hope of passing or having a look that would get me clocked most of the time I'm not sure what I would do, on the one hand It's not like I was happy with my life so almost anything would be an improvement but on the other hand the potential pain to family/friends combined with the difficulties we face in every day life would have at left me contemplating.
To sum up I want to be pretty and I'll do what I can to make it happen, this means it's important to me but I can definitely live without it like I did for 34 years.