Which is of course part of the problem - the Island is quite small, and having competing transport providers is really unhelpful.
I see the lack of a properly integrated travelcard for the island as a significant drawback to tourism.By making things much simpler for visitors you'll get an uptick in usage.
I do mean MUCH simpler, not online bonuses,freebies,codes,mobile only etc etc etc, this means a one stop ticket at point of sale(ie vending machine or travel centre) that is there in your face as an option as soon as you reach the ticket machine.
you have to remember that new visitors:
1)may not have english as a first language
2)may not be familiar with relevant websites to download apps to phones etc.
3)maybe more senior in years,so not entirely comfortable with "digital" purchases.
for the sake of a couple of extra pounds,the convenience factor will be far more important.
Sure, southern vectis will take the lions share of the revenue as they cover a much greater area, but you re then providing a choice of which mode of transport you wish to take.
for somewhere like greater london for instance, it would be a real pain in the backside if you had to buy seperate tickets for buses/underground/train.
people will pay for an all-in-one solution.(within bounds).
doesn't need much.
1 day,3 day or 7 day tickets(with single/family options) would do.if the average length of stay is 4.8 nights then most people would just buy the 7 day option anyway.
for new visitors,and old alike, making things as easy as possible means repeat business.