I know it's down to steam era operating history that Bournemouth was where the electric service also ended in 1967, but I've always thought that from an operating and service point of view Poole would have made a better terminating point for the electric service in 1967. Especially as the conductor rail already went half way to Poole - as far as Branksome to allow access to Bournemouth T&RSMD !
Poole was growing rapidly from the mid-1960s so the business potential would probably have been there. Best guess - one sub-station at Poole and a track paralleling hut at Parkstone, plus four route miles of conductor rail. Until electrification was extended to Weymouth in 1987/88 the BR(S) service to Poole was pretty poor with, generally, only one train an hour in each direction. A missed opportunity I feel.