The U shaped galley is by far the easiest to work in, and the safest, but even with the U shape some other handholds are a great help and safety feature. I have looked at a lot of boats lately and one thing that seems to be lacking is handholds, about the only ones that I see them in is racing boats. You might look at the racers and adopt some of their ideas. They are there for good reasons.
One reason for RO water tasting different is lack of minerals and it picks up flavors from what it travels through. You can add some bottled water and use either teflon food quality tubing, which is best, or SS. Both will minimize any added taste.
Who is building your boat ?