As I wrote the best choice would be a CODAG, turbines for top speed and diesel for economy speed, but also electric propulsion, gas turbine generator, or electric-motor diesel generator would be a great choice.I think a better option than the 8 diesels with their associated undesirable large penalties of weight and complexity,not to mention all the extra space required if one goes for a mechanical shaft drive arraignment rather than an electric drive,would be to look at marinising one of mapnas gas turbine sets,something like the mgt-30 would be an excellent choice with its 25mw+ output.
Another option would be marinising locomotive diesel electric generator sets for naval use.
Personally I think that combined diesel and gas electric is the way of the future for warships.
I think that one of the biggest impediments to the future development of the navy and its blue water fleet is the extreme conservativeness on the part of avy when it comes to warship design and also its fixation upon the big items such as hulls while neglecting the equally important ancillary systems that are going to go into and on that hull,ie the failure to develop a credible naval sam system or even a much simpler ciws before these ships went into service,ideally these systems would`ve been designed,built and tested in parallel with the construction of the rest of the ship.
But for both of them you have to master the technology perfectly.
It is not easy to naval gas turbines, very few nations have developed these capabilities, ditto for electric propulsion.
Therefore my hypothesis of 8 diesel engines was only a low risk choice, since in the CODAD version with 4 diesel engines it has already been tested on at least the SAHAND 74, a possible choice, if the others are not viable.