It comes back to balance of course. I thought the use of Timani as a midfield battering ram was astute one given who else was in the side i.e Sharpe the master lineout tactician, Dennis and Higgers having good skills in this area also. Kane jumps, and jumps well I think, I can't remember him performing poorly at all in the lineout in Super rugby. Horwill jumps well also. Timani will be required to hone that aspect of his game (cause most of the rest seems to be coming along nicely). Add to that Pyle and Neville (who both remind me so much of sharpe in his play but with twice the natural athleticism) and Simmons who is serviceable at Test level we'll be good here for now and a while to come.
So as it stands we will use Sharpe paired with Douglas, Timani and Simmons for now, with the future options shaping up to be Horwill, Timani, Douglas, Pyle, Neville and Simmons. With such a wealth of talented options we will be in a good spot, so I think the determining factor will be how the back row looks. For example, a returning Cliff Palu would probably assume the role of midfield battering ram, possibly taking away some of timani's appeal (unless he begins to compete with horwill and douglas in terms of lineout nous and tackling/breakdown work rate) and making douglas an appealing option. If Dennis remains in a lineout role this changes things again etc.
This is fun to muse upon