tube challenge speed or stations route planning conundrum..

Ok, I’m planning my route for an attempt at the 270 completion of the tube challenge on March 9th ... Morden starting line, finishing up at Brixton.... (this is based on night tube and getting back to the hotel after I finish)

starting at Morden, taking a Charing Cross branch train up to High Barnet (taking in the Mill Hill East branch on the way up), then a 384 bus across to Cockfosters. Down to Finsbury Park and out to Walthamstow Central at the top of the Victoria line... doubling back on ourselves to Finsbury Park....

now at that point , do we continue on the Victoria line to King’s Cross St Pancras (ticking off the 1 station in between, namely Highbury & Islington) or change for the Piccadilly to tick off Arsenal, Holloway Road and Caledonian Road in between?? The Victoria line will be quicker, but the Piccadilly has 3 stations to 1 between Finsbury Park and King’s Cross St Pancras... speed or stations?? which would you recommend, considering we have to tick off the station or stations on the other line at some point

Edit:- removed the email .sig etc (copied from an email sent to my brother)