I would recommend putting in a larger version of the twist 2 clean by Lakos. Is there a reason you cant manually clean it occassionally? I have never been impressed with the Rusco version. They are ok, but the filters dont really clean themselves that well.
And your idea for a timer initiated blowdown with a standard solenoid is fine. The Rusco is a ball valve, these are less prone to water hammer and fouling with chunks of debris that this filter is designed to take out.