Unfortunately you are right, i bet they would settle on smaller instead of slower under the "system warfare" doctrine.
On the other hand, the LM2500 used on Oliver Perry Class has only got 16MW power, shouldn't it be the step before AB's upgrated 20MW (if that offers some consolation to Shenyang Liming)?
And I quite agree with what tphuang pointed out. 054A is a milestone for PLAN's progress towards the blue water ambition. We didn't see that many actions from PLAN ships (mainly engaged in diplomatic/ceremonial missions) before the anti-pirates compaigne, they would never have learned about what a modern navy does, especially thousands of miles away from the base, with ships decades behind contemporary tech. standard. 054A is not perfect yet has got it all, for PLAN sailers the upgrade to 054A is like getting the first car after graduation, a huge step towards the realisation of mercedes dream