Batch 1 and 2 42's were a bit shorter and lighter than desirable and I've certainly heard it said that a number of the cost cutting moves were aimed at making it more exportable.
Just to refresh your memory on the 42 :
Type 42 destroyer - Wikipedia, the free encyclopedia
More authoritative is this link
Type 42
You will I hope, acknowledge the point repeatedly made in both articles that the larger, heavier and more expensive batch threes demonstrated far better sea keeping, and were more survivable due to the displacement of key systems from close proximity to one another.
It bears considerably on your earlier suggestions the RN builds a fleet of corvette size vessels.
I'm not having a pop at the 42's - for the time they were designed for, they were pretty competitive designs and have remained useful for much of their life.
Finally I did not say that the RN should order what they *like* - they are (duty bound!) to order what they feel they need for the task at hand. Unfortunately the RN, like the US and Australia to name a few similar users, need ships with a good range - a global reach - and that driver shapes the propulsion and fuel reserves of the ship. Most of the export markets we'd need to break back into are in need of vessels with only a regional reach, can be smaller and with a shorter range, as well as overall cheaper as they can be locally built, often under licence.
The ships we need for our own purposes are driven by a global commitment and other users with similar requirements already design and build their own equivalents.
We're also in competition with other ship builders who's labour costs and native requirements are more attractive - I can't see us being able to sell a native build high end escort as most of the customers out there want to license build.
Navantia, with a solid design of a good general purpose hull, and lower labour costs than the UK, has mostly made license sales - not complete hulls for instance.
I can't see why the Type 26 can't be made attractive as a license build option however - providing some imagination and flair are applied.
Ian