raised beds - is much more than esthetic choise imho. its an adaption from farming technique to gardening. there is tremendous benefits from using them over pots, but also they need more work. the beds give space for the plants to grow as big as they can, with no limits in the root-zone.
i grow only in raised beds with amended soil. imho this is really helpfull for us who live in places with longer seasons since the plants keep producing well for a long time. more soil means more nutrient and humidity reserves and should in most cases increase also yields.
rasiedbeds make sure the root area of the bushes dont heat up as much as they would do in pots.
the amount of plants per raised bed depends on variety, plants that can grow big need to get spaced apart a bit more than small plants. for example i keep my TSMB's at about 1m distance from each other, since when fully mature they will all be reaching about 1,5m heigth and circumference about 1m. meanwhile the zanahoria triangulos who grow really tiny bushes, i plant at distance of about 40cm.
some baccatums grow huge in the soil and should be on good distance to other plants, not to shade them..
takes a bit more planning, since you will have to have in mind the potential size of varieties and their sun and watering needs, since once they are palnted in the ground there is not much left to do.
...also i make sure not to mix varieties in one raised bed to avoid to have plants with different hydric needs growing together..
hope it helps.