From: San Antonio, TX
I am playing Scen 28 (DDB-C), and the IJN CSs are generally not available to convert to CVL until after 11/42. It takes 300 days. I am curious: Do you convert them, or not?
There is no question they are more valuable units as CVL than CS. The problem is you can't snap your fingers and make it so.
Those 300 days, from 11/42 through 8/43, are a critical time for the IJN. Late 1943 is as well, but by the time 1944 rolls around it's debateable whether a couple more CVLs are going to matter. You could argue those 300 days means they come back too late to make a difference.
In the meantime, the CS is not useless; you can pack it with RUFES for extra CAP. You can pack it with Jakes to take pressure off DBs for search. You can do one of each! They also have some AA to provide.
My gut tells me to leave them be, but I am curious what others think. It's a tough call, because some more CVLs are clearly better. I suppose you can split the difference, converting Chitose/Chiyoda but keeping Nisshin, which can't convert until 12/42.
As an aside, not even sure what to do with Mizuho. The speed is a killer, only fit to run with CVEs. I suppose that's the role.
What do you think?
Q-ball, there was a thread on this topic approximately 2 months ago. You may want to do a search for it. Consensus was all over the place for the reasons you identify.
Several people (myself included) keep Mizuho for floatplane group expansion, floatplane training and / or Tanker convoy support.