If Mars likes to cut and dissect, Venus is about beauty and union. It represents relating and relationships, love, romance and adjacent concepts such as pleasure, manners, sensations, art, music, fashion and food.
On a less material/visible and more abstract level, Venus rules over everything that feels silky, milky, gentle, lush, shiny, glittery and calming. It represents the things we value in life which is why it is often associated with money, finance and the stock market. The things we value are the things we love hence the relationship with love and romance. Also, Venus rules over objects of value such as works of art, luxurious items, branded goods etc.
In Ancient Greece, beauty was associated with harmony and harmony was another word for balance. It was impossible for things to be beautiful if they lacked balanced features. Going to extremes or viewing issues from one perspective only are attributes that run counter to Venusian values. Venus likes to harmonize its environment by glossing over differences.
Manners, diplomacy and tact are signature Venusian domains. If Mars wants to fight and win, Venus wants to build relationships on the basis of cooperation, not competition. If Mars likes to take initiative, Venus likes to adjust the disbalances that occur along the way. Unpleasant situations are swept under the carpet, open conflicts are avoided like the plague.
Venus values poise and decorum because they are the behavioral expression of beauty. If Mars likes to shake things up, Venus prefers to keep the peace by keeping things as they are. Small changes are welcome, radical variations feel unnatural. Problems are fixed by tweaking the status quo, not by overhauling the whole system. This adherence to the status quo is why Venus-ruled Taurus is often associated with habits, traditions and stagnation.
In final review, Venus is ultimately about pleasure and everything that partakes in it, precedes it and maintains it. It rules over expensive gourmet dinners, sensual caresses, sweet romance, courteous manners, silky-smooth bed linen, the artistic decoration, the classy wine, the love-making. Beauty underlies these experiences. Money is the practice prerequisite for them. Harmony and diplomacy protect it.