Hi
I'm planning some work in our laundry over the school holidays. For perspective, the room layout is:

Hopefully my writing is legible over the graph pad squares.
The area I want to work on looks like this:

Please excuse the mess!
Our cat's litter tray sits on the newspaper and the cupboard behind it is hardly used.
This is what I'm thinking of doing:

So I'd be installing a bench (stretching across the area), replacing the basic shelves with open cube shelves and replacing the sink cupboard with a simple front cover (just enough to hide the plumbing) so that the litter tray could sit underneath the sink, out of the way. I'd also paint the walls (I narrowed the colour down to a couple of nice pale greys at Bunnings today).
Question 1: What would be the best way to install the new shelves? I'm thinking I'll have to make them first. I had a look at the cube shelves in Bunnings and they don't work for the space (size wise).
Question 2 (this is probably one for a plumber): Is it possible to change the layout of the pipes (see below), to give more clearance? I.e. lift it all up. We have a tall cat!

I'm also thinking that replacing the internal door with a barn style one might be a good way to create some space.
Possible tile and bench wood combo:

Regards
Melanie