To be contrary all mainstream martin 000 and 00 guitars are 24.9 scale length. Martin OM, M, D and 0000 variants all have the longer scale length at 25.5

Martin Simpson uses medium gauge strings, but as he always uses a 14 rather than 13 gauge top string to compensate for the top string being de tuned to D. Martin Carthy uses strings that most mortals could not even finger the are so heavy.

Some small scale manufacturers make a DADGAD set on a similar basis to equal out string tensions.

In my case I use 52 to 11 strings on both my guitars, but the one I use most for open tunings has a slightly different bridge profile, being higher on the top two and base strings. There is a lot of difference between makes. I find Elixir to slack in tension on wound and plain strings, no recommendation intended but D Dario's suit my guitars and me and are consistent.