I rode on a Pulsar 2 this morning and I can confirm that there is no visible hump in the floor, only a sunken gangway.
From memory, the Wright Eclipse Urban also doesn't have a visible hump, whereas the Scania L94UB Wright Solars do have a row of backwards-facing seats, and therefore by inference, a hump on the interior. I suppose most of the buses that don't have humps get away with it because they are single deckers, and usually on a heavyweight chassis, so are often relatively tall. For instance, the Scania Omnilink is substantially taller than the Omnicity, and therefore has no visible wheel hump, leading to no backwards seats.
I must now mention the Mercedes-Benz Citaro O530, specifically of Kinchbus, which had five but now have only two left. On the nearside, over the wheel, there was a pair of backwards-facing seats, one of which was mounted higher than the other, but was shorter than the aisle seat, although the backrests were in some examples switched around so that the window seat looked very much higher than the aisle seat! Behind that is a row of three longitudinal seats. On the offside is one pair of backwards-facing seats, again over the wheel, followed by another pair of backwards facing seats, and then a pair of forwards-facing seats in front of the engine compartment. At the very back is a row of four seats, offset to the nearside due to the engine compartment on the right, which had a luggage rack on top. Truly bizarre.