I was worried by some of the suggestions of very small vessels, but yes, Arrowhead looks promising, & Leander's in a class which still seems to be attractive to some navies. It's about the same size as the ANZACs, or marginally bigger. I'd prefer something like FTI, though: just that bit more room to fit everything in.
I'm also split on it. Type 26 was supposed to be reasonably priced, especially with carrying over equipment from updated T23s, but it's turning out much more expensive (where did all the money go?). But for that increase, I'd say no argument, just build GP T26s. But given the price of T26, a cheaper hull looks attractive. It actually looks possible to save money even with the cost of setting up, & even if it costs a bit more than £250 mn.
Exportability? Well,there's a market for warships smaller than T26, as TKMS, Damen, etc. show.