If you have a good chartplotter on your pedestal, and if all your sensors are networked, then you can have the data displayed in front of you (with the layout customized on the screen). This will save money and minimize the number of holes for individual displays. Personally, I chose the other route: my depth, speed and wind are on the cabin bulkhead, for everyone in the cockpit to see. I think that this decreases the chances of running aground or gybing accidentally. I thought long and hard about this, because drilling big holes in my boat is always traumatic, no matter how many times I've done it.
An anecdote: one of our Club members is going all-out with new electronics on his 30-footer. Some guy talked him into installing a 12-inch touchscreen chartplotter on the bulkhead where he can't reach it from the wheel. The cutout is enormous. I tried to talk him out of it.
Here's my view from the helm. Note that I mounted my old Garmin 78sc on the side. It displays nav info: GPS speed, distance to mark, VMG, bearing, compass rose. Saves real estate on the main 9-inch screen. Powered from the house bank, of course.
View attachment 38828