Would be nice if it were possible.
Skytower is not really an option as last i heard there was a prety long waiting list for spots. also the costs is prety high.
Feltex building in AK, Symond Street is prety much the same as is the Clear POP building in Penrose. (unless you have an office with antenna rights).
Water Towers are a great idea but usually surrounded by trees these days and often in fringe areas.
Using Vodaphone is not an option as this would be seen as a conflict of interest and could damage relationships between them and their current business partners.
However. Possible options is it were to be a Community Based project could include setting up our own towers. There are still regulations that come into play but because its a public project council's are required to assist and with the right amount of local support the local boddies dont get much say in the matter.
Schools would be another alternative. Offer the schools 802.11 connectivity in exchange for a 2 level tower system that provices one level for the school to use the other is public access.
We have a power backbone that requires "Iron Giants" the towers that carry primay power feeds. One issue here is that you need a cable that goes down to ground and would need some form of arcover protection should something go wron on the tower or should the mosture in the air enable the HVDC to arc over to your antenna.
But i do agree, we really need to get together and combine our efforts.
Regards
Andrew