I think this issue could be overcome by a proxy/delegate style system. With the ability to change proxy/delegate at any time, we would have ongoing accountability and move away from the problems of election cycles. Even better from a representation viewpoint (but more complex from a design viewpoint) is the option to have different proxies/delegates for different decisions/topics.

The real problem is balancing tradeoffs, particularly between spending and taxes. Currently (in Australia at least) the size of the expected budget defecit is a crude metric for the overall financial responsibility of the government and is a factor in elections. If citizens can vote independently for spending versus taxes, then there is nobody to hold accountable (tragedy of the commons).