Married men / women, what’s your advice on this - what factors should one consider while evaluting a to-be spouse?

Ignore conventional wisdom and advice. Watch this video for a better approach -

https://youtu.be/EYXZmPb6cYA?si=RlA3UgLYq6D8_gDT

Comfortable silence

Whatever your criteria and method of figuring your partner, in a few months it doesn't matter.

Like a learned elder once said - Love marriage is suicide, arranged marriage is homicide. The end result is the same.

It's very difficult to give generic advice as marriage is a very personal decision. I'll share some pointers based on my experience :

1. Self-awareness. Please know yourself and your expectations are from your spouse. We're all different individuals. Marriages are not surviving because people are realising later in life that they're not happy with what they signed up for. See what works for you and if it doesn't can you make it work?
2. Stop being a mind-reader or Over-critical : If you have insecurities about your looks or credentials or anything else, please try and approach the other person with an open mind and optimistic ally. I know you've had rejections which makes you question the process and you feel like it's a pain to go on these dates to meet new people, but hang in there. It might take time but eventually if you keep trying you might end up finding someone you can sync with. Delaying by a year or 2 is better than being stuck with someone toxic for the rest of your life.
3. Whatever people might say, status-caste-religion-Seema-Aunty etc etc , there are no shortcuts or formulas or the-right-way to go about marriage. Find what you and your family are comfortable with. If you do choose to defy societal norms, have the courage to see it through else it'll take a toll on your mental peace.
4. A good marker early on in dating is if you can talk effortlessly, there might be a chance to build into a good relationship. If you can't stand or talk , it'll be difficult. I personally used to cut short such dates and move on to other people. Also, don't have too many parallel people to meet. It might get pretty messed up. Remember, in the end, it should make you happy to begin a new phase of your life. Good luck!

I think generally folks look at common interests but I have felt that more than commonality in interests, commonality in the value system is very critical. Once your levels of values are common then any kind of differences can be handled. You gotta notice these values in small everyday subtle things. How kind, honest, trustworthy, respectful someone is.