If it's shallow to consider appearance in a romantic partner it's just as shallow to consider taste when eating. It's an integral part of the experience. Would you say you loved a food based solely on its nutritional content even if you threw up every time you ate it because of how bad it tasted?
I think too many people put too great a focus on individual aspects when judging the value of a partner. Yes, it would be shallow to only consider appearance but it would also be shallow to completely disregard it as well.
Not only does that approach diminish a crucial aspect of the relationship - the pleasure provided by looking at your partner - it also diminishes the self esteem bonuses it provides in being with someone you find attractive and finds you attractive as well.

I don't think it is shallow just a preference on what you like. However here is a question for you. If this person you get a long with , share hobbies with, have fun with as a great friend the only think holding you back from dating them is lets say a little extra weight. Would you date them as the weight is the only thing you don't find attractive? Or say a big nose?

I have also found that some men start to look more attractive once you get to know them more, or maybe it is just that some things can become over looked as you get to know someone.

It's a combination of looks and what's inside. You can never have a relationship based on looks alone. And if you're just meeting someone, physical attraction is very important. Someone may be beautiful to you are unattractive to someone else. We all see different things in people, look at it with the open mine.

I think you must ask yourself how you would feel waking up next to the person for the foreseeable future. The more you care about someone, the less looks matter, but they still matter.

I hope not, because I've become absolutely ruthless with respect to online dating. If there's even a second's hesitation on attractiveness, I swipe left. Let's face it, there are soooo many people out there, why not search for the perfect match? Now if this strategy doesn't pan out in a year or so I may loosen my restrictions lol.

Immediate attraction without a word, it's after you start talking that can be the problem

We are all attracted to certain faces or body shapes. What one individual finds attractive will be different from what another person is attracted to. it's all a part of the dynamic of chemistry.