I am going to my first conference at my new job next week. It is a a 4-day event in Philadelphia, PA, and the weather is supposed to be relatively nice, tough it may rain occasionally. I am traveling by train, and thus have no luggage restrictions - I do not need to pack a tight mix and match capsule, I can pack different outfits for each day if I want. What I need are four regular conference outfits, one outfit for the closing gala ceremony, one casual travel outfit and perhaps another casual one if I get an evening or two off.
Unlike my previous conferences when I presented my research, the main purpose now is to meet lots of scientists, and network with them in my new job capacity ( my job will require constant interactions with professors and scientists) - in a way I will be introducing myself to these people. I need to establish working relationships, and need to inspire respect. I will be turning 40 next month, but am often mistaken for someone about 10 years younger; and the majority of people I will be interacting are older men. Thus I need to leave good impression as someone who is competent and knowledgeable despite my age.
My mentor gave me lots of excellent advice, and when it comes to dressing specifically, he said to dress one level of formality below full suit. He would typically wear blazer and pants that are not parts of matching suit, shirt and tie, and maybe loose the tie in the evenings. I am trying to figure out the exact female equivalents to this outfit formula. Obviously, one version would be a blazer, pants or pencil skirt that go with the jacket but do not match it exactly, blouse and dressy shoes. I am unsure about what the best topper for a dress would be to achieve the same level of formality: does a jacket have to be different color from the dress, would the same color be too "suit-like", would a cardigan work or be too casual etc. I have three dresses attached in the finds below that I am trying to figure out right toppers for. Some potential toppers are in the second row. Third row shows the dress I intend to wear to the gala and some shoes. I will pack some separates, too, but am mostly basing my travel wardrobe on dresses. I am keeping the colors super simple with black base and light grey, white and blush accents. I am also curious about jacket length for pencil skirts and sheath dresses - I know and the follow the rule that skirts and dresses in general need short/cropped toppers, but have a feeling that one may be able to get away with longer (the length one would wear with pants) jackets with pencil skirts and sheath dresses due to their sleek shape.
Finally, I would also appreciate any packing tips and tricks to keep suiting pieces and silk blouses from wrinkling. Many thanks!

ETA: photos of some possibilities added. I am discussing them further below. Please excuses some wrinkle and random streaks in some of the photos.