Vegetables – difference between a vegetable tray and a relish tray

What gives spices their flavors are the oils that they contain, along with any water soluble flavors that they might have. In a pressure cooker, your food will cook hot. What that means to your spices will vary as certain spices could grow more bitter or sweeter depending on the compounds inside them. Conventional wisdom says that pressure cooking concentrates the flavors, although that would seem to fly in the face of physics as you aren't reducing while pressure cooking, you are just heating steam at a higher atmosphere to transfer more heat to the food faster.

As for texture, use the one that you like.

To boil vegetables, you add the vegetables to a pot of water, and boil the water for a short duration until the vegetables are sufficiently cooked. One may add salt or other flavorings (such as broth, as you mentioned) to the water prior to boiling.

Steamed vegetables are cooked in a steamer basket, where the vegetables are not in the water, but are instead sitting above the water, and are thus cooked by steam.

Salt must be added to steamed vegetables after they are cooked rather than to the water prior to cooking, since salt does not evaporate.

Steamed vegetables can retain more of their original flavor and nutrients, since they do not leech out into the water during boiling. On the other hand, you cannot add additional flavors to your vegetables during steaming--since flavors cannot soak into the vegetables from the water, either.

Which taste/texture you prefer, of course, can be a matter of personal opinion.

In my experience, boiled vegetables are often mistakenly referred to as steamed vegetables. And often, many restaurants will sell "steamed vegetables" which are really just microwaved frozen vegetables, which may strictly be steamed (it certainly isn't boiled!), but really bears little resemblance to the true steaming process (and has relatively poor flavor, as well).