R
Richardk
Its a matter of personal preference but if it were me I'd fix them landscape. You could increase the size of the thin cut under the cill by dot n dabbing some plasterboard onto the cill, levelling it up at the same time. Setting out is an important first step. Take each wall in isolation. As has been said, mark a centre line under the hob and with a grout line on this c/l, see how the cuts will be at each end of the wall, up the sides of the wall units, and at the sockets. If too many awkward cuts, set out from a half tile on the c/l and see if its any better. Do the same for the window wall.