Well I am not interested in playing in Martin Carthys tuning or sounding like him,excellent though he is.
I find light strings work very well,with my guitar,and for the tunings that I am using, double drop d,drop d, standard, in fact I was advised by an instrument maker not to use heavy strings on my particular guitar.
mind you none of them work very well on the Concertina.
yours, highly strung, Dick Miles