Well, the way would be by far the most direct means between Ryde and the Sandown-Shanklin conurbation, which would allow for fast, attractive and reliable bus times, and given a bus's infinitely quicker ability to brake, uplift / set down custom and accelerate again, a by far better means of attracting intermediate custom to those settlements too. It would also allow for other through journey opportunities too, such as faster links between Ventnor (where buses actually get into the town centre and seafront, not a mile away and with a descent the size of Everest like the old railway station greeted people with) and Ryde, and on the existing route 2 / 3 for trips between Newport and Sandown / Shanklin.
Some form of integrated ticketing would probably help tide the Island line over in the mean time (though there is of course no incentive whatsoever for SV to offer it), however that doesn't remove the gargantuan elephant in the room that is how utterly shot at the railway line is. The rolling stock, as wonderful as the nostalgia is, is a complete embarrassment, and the infrastructure upon which it runs are in little better state. Couple that with two structures bookending the main settlement on the line (Ryde Tunnel and Pier) which royally screw any traditional solutions and you have a problem which will not be solved simply by throwing scores of money at it and repeating 'vital social necessity' in the hope that the railway gods take pity on it.
Like many other areas on the British rail network in the past, the perpetual lack of decisive, modern solutions will do nothing except deeper entrench its problems. As much as I love both railways and the Isle of Wight, I just do not see where how the existing Island line resolves itself of these problems in its current form.