High tyre pressures reduce the likelihood of a puncture occurring from the tyre being pinched but also carry a potential higher risk of being punctured by a sharp edge or debris than a lower pressure, so there is no perfect pressure but a compromise between the two extremes is likely to give the best puncture resistance. You can use a retail website such as blackcircles.com to view a wide range of tyres in the required size which also shows the economy rating, but ride quality is typically determined by the aspect ratio or sidewall size of a tyre in relation to its overall size and tyre pressures. You may also wish to consider fitting smaller wheels, as these would typically have a taller sidewall for better ride quality and less width, which usually means lower rolling resistance and therefore better fuel economy.