The LaSalle and Delray look like they are on the same last and are on a different last from the Parkway. The Strand is on a different last. Comfort really depends on how well a particular last fits your feet, so the best thing to do is to try them on.
I think that black or dark brown are the best shoe colors if you are wearing a suit and tie, but if you are wearing odd jackets and trousers with no tie, you have a bit more flexibility in both design and color. I personally prefer chili with grey trousers as opposed to navy, but it sounds like you mostly wear grey in various shades anyways. None of those designs are going to go out of style anytime soon, so it comes down to your preference. I really like the Strand of the ones you mentioned, but you of course have to wear it. I personally dislike split toes. I don't have a good rationale for this; it's just a personal taste thing. They are a more casual feature, but your dress doesn't sound formal enough that this would be an issue.
If you want a shoe to wear with a suit and tie, the Strand is probably your best choice of them all as it is a balmoral rather than a blucher. A busy balmoral for sure, but still more formal in my mind than a split toed blucher. I'd go Park Avenue or Fifth Avenue for wear with a suit and tie, but it sounds like you don't have to do this very often and you're better off getting shoes that actually match the level of formality of your usual dress. Eventually get something more formal for when you need it, but for the sport coat and trousers sans tie look, any of the ones you mentioned are fine.
Also, have at least two pairs that you rotate (more is better). The reason is that shoes wear out much faster and get beat up more quickly when you wear them everyday and don't give them a chance to rest between wearings. Also make sure you polish them and clean them to keep them looking good.
Good luck selecting your shoes and welcome to SF.